chore: add ion package, codesight wiki, work plans, ascli config

New @boocode/ion package (v0.0.1) for inference optimization network.
.codesight/ wiki artifacts for codebase documentation.
.omo/ work plans for openspec cleanup and enhanced file panel.

.omo/drafts/openspec-cleanup.md

@@ -0,0 +1,89 @@
+# Draft: openspec-cleanup
+
+## Cross-Reference: Git Tags vs openspec Batches
+
+### Archived Stub Files — Tag Verification
+
+| Stub File | Claims Version | Actual Tag | Verdict |
+|---|---|---|---|
+| `v1.13.12-skills-audit.md` (57B) | v1.13.12 | `v1.13.14-skills-audit` | **WRONG** — off by 2 versions |
+| `v1.13.15-codecontext-synth.md` (62B) | v1.13.15 | `v1.13.15-codecontext-synth` | ✅ correct |
+| `v1.13.17-cross-repo-reads.md` (61B) | v1.13.17 | `v1.13.17-cross-repo-reads` | ✅ correct |
+| `v1.13.18-codecontext-file-path.md` (66B) | v1.13.18 | `v1.13.18-codecontext-file-path` | ✅ correct |
+| `v1.13.20-drop-legacy-cols.md` (61B) | v1.13.20 | `v1.13.20-drop-legacy-cols` | ✅ correct |
+| `v1.14-outer-loop.md` (52B) | v1.14 | `v1.14.0-outer-loop` | ⚠️ close (1.14 → 1.14.0) |
+| `v1.14.1-mcp-poc.md` (51B) | v1.14.1 | `v1.14.1-mcp-poc` | ✅ correct |
+| `v1.14.x-html-artifact-panes.md` (63B) | v1.14.x | `v1.13.19-html-artifact-panes` | **WRONG** — shipped as 1.13.19 |
+| `v1.15-mcp-multi.md` (51B) | v1.15 | `v1.15.0-mcp-multi` | ⚠️ close (1.15 → 1.15.0) |
+| `v2.0-boocoder.md` (49B) | v2.0 | `v2.0.0` | ⚠️ close (2.0 → 2.0.0) |
+| `v2.2-paseo-providers.md` (222B) | v2.2 | `v2.2-paseo-providers` | ✅ correct |
+
+### Archived Folder Entries — Tag Verification
+
+| Archived Folder | Git Tag(s) | Status |
+|---|---|---|
+| `agent-status-normalize/` | `v2.7.6-agent-status-normalize` | ✅ shipped |
+| `claude-sdk-sessionstore/` | `v2.7.5-claude-sdk-sessionstore` | ✅ shipped |
+| `contracts-ssot/` | `v2.7.13-contracts-ssot` | ✅ shipped |
+| `license-debt-mit/` | `v2.7.0-mit` | ✅ shipped |
+| `mistake-tracker-file-ledger/` | `v2.7.4-mistake-tracker-ledger` | ✅ shipped (slug differs slightly) |
+| `orchestrator/` | `v2.7.17-orchestrator` | ✅ shipped |
+| `sampling-streamjson-tokens/` | `v2.7.3-sampling-streamjson-tokens` | ✅ shipped |
+| `v2-3-provider-lifecycle/` | `v2.5.4-*` through `v2.5.13-*` | ✅ shipped (diff version numbering) |
+| `v2-6-persistent-agent-sessions/` | `v2.6.4-*`, `v2.6.8-*` | ✅ shipped |
+| `write-edit-robustness/` | `v2.7.1-write-edit-robustness` | ✅ shipped |
+
+### Misplaced Proposals in Archived/
+
+| 2026-06-07 Folder | Git Tag? | Actually Shipped? | Should Be |
+|---|---|---|---|
+| `2026-06-07-boocontext/` | **None** | No | `changes/boocontext/` (partly shipped in v2.8.0) |
+| `2026-06-07-eval-sandbox-agent-runtime/` | **None** | No | Merge into `changes/import-*` |
+| `2026-06-07-hybrid-workflow-engine/` | **None** | No | Merge into `changes/orchestrator-flow-advanced/` |
+| `2026-06-07-memory-context-engineering/` | **None** | No | Merge into `changes/memory-context/` |
+| `2026-06-07-port-audit-parlant-patterns/` | **None** | No | Merge into `changes/add-behavioral-engine/` |
+
+## Active Batches — All Uncommitted, All Unshipped
+
+All 22 active batches (changes/*/) have **zero** git tags or commits referencing them. Every batch was created locally on 2026-06-07 and exists only on the filesystem.
+
+## High-Value Prioritization (for Implementation Plan)
+
+### Tier 1: Ship in Current Batch (small scope, high value)
+1. **openspec-cleanup** — Fix folder structure: delete stubs, move misplaced proposals, add .openspec.yaml, populate config.yaml
+2. **llama-cache-and-spec** — KV cache quantization + ngram speculative decoding (llama-server arg changes only)
+3. **results-page** — New `/results` route, uses existing API endpoints
+4. **token-analyzer-ui** — New `/analytics` route, uses existing DB data
+
+### Tier 2: Current+ Batch (moderate scope)
+5. **enhanced-file-panel** — Side-by-side diff, inline comments, in-browser editing
+6. **pty-enhancements** — Exit notifications, session metadata, X-Agent-Flags
+
+### Tier 3: Next Batch (larger scope, foundation work)
+7. **memory-v2-hybrid-search** — BM25 + local embedding hybrid search
+8. **orchestrator-flow-advanced** — Trigger rules, conditional branching, HITL
+9. **omo-paseo-bridge** — OMO subagent visibility in Paseo
+
+### Tier 4: Future Batches (speculative / big effort)
+10. **add-behavioral-engine** / **audit-harness-integration** / **import-llm-evaluator** / **import-pregel-engine** — Big integration efforts
+11. **code-intelligence-upgrade** / **dev-workflow** / **conductor-evolution** — Platform work
+12. **plugin-platform** / **ui-overhaul** / **add-3tier-memory** / **add-type-inject-mcp** — Future
+
+## Scope Boundaries for This Plan
+
+**IN SCOPE:**
+- Delete 11 stub files from archived/
+- Move 5 misplaced 2026-06-07 proposals from archived/ to changes/ (with dedup)
+- Add missing .openspec.yaml to 6 active batches
+- Populate openspec/config.yaml with project context
+- Implement Tier 1-2 high-value batches:
+  - llama-cache-and-spec (llama-server args)
+  - results-page (new route, frontend)
+  - token-analyzer-ui (new route, frontend + backend)
+  - enhanced-file-panel (frontend changes)
+  - pty-enhancements (backend changes)
+
+**OUT OF SCOPE:**
+- Tier 3-4 batches (future planning)
+- Full behavioral engine or Pregel state machine integration
+- Plugin platform architecture

.omo/plans/enhanced-file-panel.md

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+# Enhanced File Panel — Implementation Plan
+
+## TL;DR
+
+> **Quick Summary**: Add side-by-side diff, hide whitespace, wrap lines, expand all files, inline diff comments, and in-browser file editing to BooCode's right-rail file panel.
+>
+> **Deliverables**:
+> - Enhanced `GitDiffView.tsx` with toolbar (layout/whitespace/wrap/expand-all toggles)
+> - Split-layout diff renderer (side-by-side)
+> - `useDiffPreferences` hook (localStorage persistence)
+> - Inline diff comment components + Zustand store
+> - File editing mode in file tree + server write endpoint
+> - Server `git diff -w` support
+>
+> **Estimated Effort**: Medium-Large
+> **Parallel Execution**: YES — 4 waves
+> **Critical Path**: Wave 1 (server) → Wave 2 (diff preferences + toolbar) → Wave 3 (split layout) → Wave 4 (comments + editing)
+
+---
+
+## Context
+
+### Original Request
+User wants to implement these features from Paseo into BooCode's file manager:
+1. Unified diff ✅ (exists) / Side by side diff ❌
+2. Hide whitespace ❌
+3. Wrap long lines ❌
+4. Expand all files ❌ (only per-file)
+5. Refresh ✅ (exists)
+6. Comments on specific diffs ❌
+7. File edits (editing in the file browser) ❌
+
+### Research Findings
+- **Paseo** (`/opt/forks/paseo`): Best reference for all features. Key files: `diff-pane.tsx`, `diff-layout.ts`, `diff-rendering.ts`, `review/surface.tsx`, `review/store.ts`, `use-changes-preferences/`
+- **Existing BooCode files**: `GitDiffView.tsx`, `RightRail.tsx`, `useGitDiff.ts`, `git_diff.ts`, `FileViewerOverlay.tsx`
+- Key insight: None of the web references have true inline file editing in the browser — this is new ground
+
+---
+
+## Work Objectives
+
+### Core Objective
+Augment the existing file panel with side-by-side diff, whitespace/wrap/expand toggles, inline comments, and inline file editing.
+
+### Definition of Done
+- [x] `pnpm -C apps/web build` succeeds with no errors
+- [x] `pnpm -C apps/server build` succeeds with no errors
+- [ ] Side-by-side diff renders correctly (two aligned columns)
+- [ ] Hide whitespace toggles and re-fetches diff
+- [ ] Wrap lines toggles between pre / pre-wrap
+- [ ] Expand/Collapse all toggles all file diffs
+- [ ] Inline comments: click gutter → type → save → display thread
+- [ ] File edit: double-click tree → edit → save → file changes on disk
+- [ ] All preferences persist across page refresh
+
+### Must Have
+- Side-by-side diff view
+- Hide whitespace toggle (server param)
+- Wrap long lines toggle (CSS)
+- Expand/Collapse all file diffs
+- Inline diff comments with thread UI
+- In-browser file editing with save
+- Preference persistence
+
+### Must NOT Have (Guardrails)
+- No DB migration (comments are client-side)
+- No new WS frames (reuse git_diff_refresh)
+- No new `@boocode/contracts` types
+- No multi-user comment sharing
+- No git push/pull/PR operations
+- No inline hunk staging
+
+---
+
+## Verification Strategy
+
+### Test Decision
+- **Infrastructure exists**: YES (vitest for server)
+- **Automated tests**: Tests-after for new server route + `git_diff.ts` changes
+- **Agent-Executed QA**: Playwright for diff interactions, curl for API endpoints
+
+### QA Policy
+Every task includes agent-executed scenarios. Evidence saved to `.omo/evidence/`.
+
+---
+
+## Execution Strategy
+
+### Waves
+
+```
+Wave 1 (Server — foundation):
+├── Task 1: Server: whitespace param in git_diff.ts
+├── Task 2: Server: POST /api/projects/:id/write_file endpoint
+├── Task 3: Server tests for whitespace + write
+└── [tests + typecheck]
+
+Wave 2 (Frontend — preferences + toolbar):
+├── Task 4: useDiffPreferences hook (localStorage)
+├── Task 5: GitDiffView toolbar (layout/whitespace/wrap/expand-all toggles)
+├── Task 6: Wrap lines CSS + hide whitespace re-fetch
+└── [pnpm build]
+
+Wave 3 (Frontend — split layout):
+├── Task 7: Diff layout utilities (buildSplitDiffRows etc.)
+├── Task 8: Side-by-side renderer in GitDiffView
+├── Task 9: Line number gutter + alignment
+└── [pnpm build]
+
+Wave 4 (Frontend — comments + file editing):
+├── Task 10: InlineComment store (Zustand + localStorage)
+├── Task 11: InlineReviewGutterCell + InlineReviewEditor
+├── Task 12: InlineReviewThread (comment display)
+├── Task 13: File editing mode in RightRail file tree
+└── [pnpm build + full smoke test]
+```
+
+Critical Path: T1 → T2 → T4 → T5 → T7 → T8 → T10 → T11 → T12 → T13
+
+---
+
+## TODOs
+
+- [x] 1. **Server: Add `ignoreWhitespace` param to git diff**
+
+  **What to do**:
+  - In `apps/server/src/services/git_diff.ts`, add `ignoreWhitespace?: boolean` to the `getGitDiff` function signature
+  - When `ignoreWhitespace` is true, append `'-w'` to the git diff argv call in `getGitDiff` (the main diff command, not name-status)
+  - Update `GET /api/projects/:id/git/diff` route in `routes/projects.ts` to accept optional query param `whitespace=1`
+  - The param should be optional (backward compatible) — default false
+
+  **Files to modify**:
+  - `apps/server/src/services/git_diff.ts` — update `getGitDiff()` to accept and use `ignoreWhitespace`
+  - `apps/server/src/routes/projects.ts` — add `whitespace` query param
+
+  **References**:
+  - Paseo: `useCheckoutDiffQuery({ ignoreWhitespace })` passes to server → `git diff -w`
+  - Existing `git_diff.ts:36-48` `runGit` function — argv pattern to follow
+
+  **QA Scenarios**:
+  ```
+  Scenario: Diff with whitespace changes respects ignoreWhitespace param
+    Tool: Bash (curl)
+    Preconditions: A file exists with whitespace-only changes (extra spaces)
+    Steps:
+      1. GET /api/projects/:id/git/diff ⇒ verify diff_body includes whitespace changes
+      2. GET /api/projects/:id/git/diff?whitespace=1 ⇒ verify diff_body excludes whitespace-only changes
+    Expected: With whitespace=1, files that only had whitespace changes show as unchanged
+    Evidence: .omo/evidence/task-1-whitespace.txt
+  ```
+
+- [x] 2. **Server: Add POST /api/projects/:id/write_file endpoint**
+
+  **What to do**:
+  - Add `POST /api/projects/:id/write_file` route in `routes/projects.ts`
+  - Accept `{ path: string, content: string }` body
+  - Validate path via existing `pathGuard` helper (same as git discard)
+  - Write file content atomically: write to `.tmp` then `rename` the file
+  - Return `{ ok: boolean }` on success
+  - Reuse the safe file-write pattern from `services/file_ops.ts`
+
+  **Files to modify**:
+  - `apps/server/src/routes/projects.ts` — add POST route
+  - `apps/web/src/api/client.ts` — add `writeFile` method
+  - `apps/web/src/api/types.ts` — add write types if needed
+
+  **References**:
+  - `apps/server/src/services/file_ops.ts` — existing file operations pattern
+  - `apps/server/src/routes/projects.ts:544-592` — git write routes (same security pattern)
+  - `apps/server/src/services/path_guard.ts` — path validation
+
+  **QA Scenarios**:
+  ```
+  Scenario: Write file content and verify on disk
+    Tool: Bash (curl)
+    Preconditions: A project exists with a writable path
+    Steps:
+      1. POST /api/projects/:id/write_file { path: "test.txt", content: "hello" }
+      2. GET /api/projects/:id/view_file?path=test.txt
+    Expected: Status 200, view_file returns "hello"
+    Evidence: .omo/evidence/task-2-write.txt
+  ```
+
+- [x] 3. **Frontend: useDiffPreferences hook**
+
+  **What to do**:
+  - Create `apps/web/src/hooks/useDiffPreferences.ts`
+  - Define `DiffPreferences` interface: `{ layout: 'unified'|'split', wrapLines: boolean, hideWhitespace: boolean }`
+  - Default: `{ layout: 'unified', wrapLines: false, hideWhitespace: false }`
+  - Read/write to localStorage key `boocode.diff.preferences`
+  - Return `{ preferences, updatePreferences, resetPreferences }`
+  - Zod-validate on read for forward compatibility
+
+  **Files to create/modify**:
+  - Create `apps/web/src/hooks/useDiffPreferences.ts`
+
+  **References**:
+  - `/opt/forks/paseo/packages/app/src/hooks/use-changes-preferences/storage.ts` — exact pattern
+  - `apps/web/src/hooks/useProjectGit.ts` — hooks pattern in BooCode
+
+  **QA Scenarios**:
+  ```
+  Scenario: Preferences persist across page refresh
+    Tool: Playwright
+    Preconditions: Page loaded
+    Steps:
+      1. Call updatePreferences({ layout: 'split' })
+      2. Read localStorage.getItem('boocode.diff.preferences')
+      3. Reload page, read preferences again
+    Expected: layout is 'split' after reload
+    Evidence: .omo/evidence/task-3-prefs.txt
+  ```
+
+- [x] 4. **Frontend: GitDiffView toolbar with all toggles**
+
+  **What to do**:
+  - Add a toolbar row inside `GitDiffView.tsx` between the mode selector and file list
+  - Controls (left to right):
+    - **Layout toggle**: two-segment button (Unified | Split) — uses `AlignJustify` / `Columns2` icons
+    - **Hide whitespace**: toggle button — `Pilcrow` icon, active state highlights
+    - **Wrap lines**: toggle button — `WrapText` icon  
+    - **Expand/Collapse all**: toggle button — `ListChevronsUpDown` / `ListChevronsDownUp` icons
+    - **Refresh**: existing button (already present)
+  - Wire each toggle to the `useDiffPreferences` hook
+  - Expand all state: compute `allExpanded = files.every(f => expandedPaths.has(f.path))`
+  - Pass expand state as a new prop or local state
+
+  **Files to modify**:
+  - `apps/web/src/components/GitDiffView.tsx` — add toolbar section, expand-all logic
+
+  **References**:
+  - Paseo `diff-pane.tsx:1114-1273` — `DiffLayoutToggleGroup`, `DiffWhitespaceToggle`, `DiffFilesToolbar`
+  - openchamber `DiffViewToggle.tsx` — simple toggle pattern
+  - happy `InlineFileDiff.tsx:196-219` — `DiffStyleToggle` segment control
+
+  **QA Scenarios**:
+  ```
+  Scenario: All toolbar controls render and toggle
+    Tool: Playwright
+    Preconditions: Git tab active with changed files
+    Steps:
+      1. Verify layout toggle shows "Unified" / "Split" buttons
+      2. Click "Split" — verify visual change
+      3. Click "Wrap" — verify wrap toggle
+      4. Click "Expand all" — verify all files expand
+      5. Click "Collapse all" — verify all files collapse
+    Expected: Each toggle works and updates state
+    Evidence: .omo/evidence/task-4-toolbar.png
+  ```
+
+- [x] 5. **Frontend: Diff layout utilities + side-by-side renderer**
+
+  **What to do**:
+  - Create `apps/web/src/utils/diff-layout.ts` with pure functions:
+    - `buildNumberedDiffHunks(diffBody: string): NumberedDiffHunk[]` — parse diff text into hunks with old/new line numbers
+    - `buildUnifiedDiffLines(file): UnifiedDiffDisplayLine[]` — existing behavior
+    - `buildSplitDiffRows(file): SplitDiffRow[]` — pair removals/additions into left/right rows
+  - Create `apps/web/src/components/DiffSplitView.tsx` — the side-by-side renderer:
+    - Two columns (left = deletions, right = additions) with a thin divider
+    - Each column has its own gutter (line numbers) + code content
+    - Use Shiki `codeToHtml(language)` for syntax highlighting per side
+    - Handle empty cells (unpaired lines render as blank)
+  - In `GitDiffView.tsx`, when `layout === 'split'`, render `DiffSplitView` instead of the unified diff body
+
+  **Files to create/modify**:
+  - Create `apps/web/src/utils/diff-layout.ts`
+  - Create `apps/web/src/components/DiffSplitView.tsx`
+  - Modify `apps/web/src/components/GitDiffView.tsx` — add layout branching
+
+  **References**:
+  - `/opt/forks/paseo/packages/app/src/utils/diff-layout.ts` — full algorithm
+  - `/opt/forks/paseo/packages/app/src/git/diff-pane.tsx:968-989` — split layout rendering
+  - existing `git_diff.ts` `splitDiffByFile` — already splits unified diff per file
+
+  **QA Scenarios**:
+  ```
+  Scenario: Side-by-side diff renders correctly
+    Tool: Playwright
+    Preconditions: Git tab active, files with changes
+    Steps:
+      1. Click "Split" layout toggle
+      2. Verify two columns appear with a divider
+      3. Verify deleted lines are on left side (red background)
+      4. Verify added lines are on right side (green background)
+      5. Verify context lines appear on both sides, aligned
+    Expected: Layout matches Paseo's split diff
+    Evidence: .omo/evidence/task-5-splitdiff.png
+  ```
+
+- [x] 6. **Frontend: Inline comment store + Zustand**
+
+  **What to do**:
+  - Create `apps/web/src/stores/useDiffCommentStore.ts`
+  - Define `DiffComment` interface: `{ id, filePath, side, lineNumber, body, createdAt, updatedAt }`
+  - Create Zustand store with:
+    - `commentsByKey: Map<string, DiffComment[]>` keyed by `${sessionId}:${mode}:${filePath}`
+    - `addComment(key, comment)` / `updateComment(key, id, body)` / `deleteComment(key, id)`
+    - `loadComments(key)` — load from localStorage
+    - `persist()` — subscribe to store changes, write to localStorage key `boocode.diff.comments.[key]`
+  - Export `useDiffCommentStore`
+
+  **Files to create**:
+  - Create `apps/web/src/stores/useDiffCommentStore.ts`
+
+  **References**:
+  - `/opt/forks/paseo/packages/app/src/review/store.ts` — zustand store for comments
+  - `/opt/forks/paseo/packages/app/src/review/state.ts` — CRUD operations
+
+  **QA Scenarios**:
+  ```
+  Scenario: Comments persist across page refresh
+    Tool: Playwright
+    Preconditions: Diff panel open with changes
+    Steps:
+      1. Add comment on a diff line
+      2. Verify comment thread appears
+      3. Reload page
+      4. Navigate to same diff
+    Expected: Comment thread still visible after reload
+    Evidence: .omo/evidence/task-6-comment-store.txt
+  ```
+
+- [x] 7. **Frontend: InlineReviewGutterCell + InlineReviewEditor**
+
+  **What to do**:
+  - Create `apps/web/src/components/InlineReviewGutterCell.tsx`:
+    - Replaces the plain line-number display in diff rows
+    - Shows line number + "+" icon on hover (to start a comment)
+    - Uses `ReviewableDiffTarget { filePath, side, lineNumber }` for tracking
+  - Create `apps/web/src/components/InlineReviewEditor.tsx`:
+    - Textarea with placeholder "Add comment..."
+    - Save (Ctrl+Enter) / Cancel (Escape) buttons
+    - Animates in below the target line
+  - Integrate into `GitDiffView.tsx` — gutter cells render in the diff line view
+  - Wire to `useDiffCommentStore`
+
+  **Files to create/modify**:
+  - Create `apps/web/src/components/InlineReviewGutterCell.tsx`
+  - Create `apps/web/src/components/InlineReviewEditor.tsx`
+  - Modify `apps/web/src/components/GitDiffView.tsx` — integrate gutter cells
+
+  **References**:
+  - Paseo `review/surface.tsx:245-309` — `DiffGutterCell` + `InlineReviewGutterCell`
+  - Paseo `InlineReviewEditor` pattern
+
+  **QA Scenarios**:
+  ```
+  Scenario: Create inline comment on diff line
+    Tool: Playwright
+    Preconditions: Git tab, file expanded
+    Steps:
+      1. Hover over a gutter cell
+      2. Click "+" button
+      3. Type comment text
+      4. Click Save (or Ctrl+Enter)
+    Expected: Comment thread appears below the line
+    Evidence: .omo/evidence/task-7-comment-create.png
+  ```
+
+- [x] 8. **Frontend: InlineReviewThread component**
+
+  **What to do**:
+  - Create `apps/web/src/components/InlineReviewThread.tsx`:
+    - Renders below a diff line when comments exist for that target
+    - Each comment shown as a card: avatar placeholder, body, timestamp, edit/delete actions
+    - Collapsed state shows comment count badge
+    - Expanded state shows full thread
+  - Integrate into `GitDiffView.tsx` below diff line rows
+
+  **Files to create/modify**:
+  - Create `apps/web/src/components/InlineReviewThread.tsx`
+  - Modify `apps/web/src/components/GitDiffView.tsx` — render thread below lines
+
+  **Reference**:
+  - Paseo `review/surface.tsx:537-573` — `InlineReviewThreadContent`
+
+  **QA Scenarios**:
+  ```
+  Scenario: Comment thread displays and supports edit/delete
+    Tool: Playwright
+    Preconditions: Comments exist on a diff line
+    Steps:
+      1. Expand comment thread
+      2. Verify comment body is visible with timestamp
+      3. Click edit → modify text → save
+      4. Click delete → verify comment removed
+    Expected: Full CRUD works on comments
+    Evidence: .omo/evidence/task-8-thread.png
+  ```
+
+- [x] 9. **Frontend: File editing in the file tree**
+
+  **What to do**:
+  - In `RightRail.tsx`, add a file edit mode:
+    - Double-click a file in the tree (or context menu "Edit") enters edit mode
+    - The file row transforms: file name becomes a monospace textarea pre-filled with file content (fetched via existing `api.projects.viewFile`)
+    - The row shows Save / Cancel buttons
+    - Save: calls `api.projects.writeFile(projectId, path, content)` — the new endpoint from Task 2
+    - Cancel: reverts to the original content and exits edit mode
+    - After save: re-fetch the file tree + emit `git_diff_refresh`
+  - Only one file editable at a time (close any existing editor before opening new)
+  - Visual indicator (highlighted row) when in edit mode
+
+  **Files to modify**:
+  - `apps/web/src/components/RightRail.tsx` — add edit mode state, edit UI
+  - `apps/web/src/api/client.ts` — add `writeFile` method (from Task 2)
+  - `apps/web/src/components/TreeLevel.tsx` (inline in RightRail) — accept edit mode props
+
+  **References**:
+  - Existing `RightRail.tsx:170-175` `openFile` function — pattern for file interaction
+  - Existing `FileViewerOverlay.tsx` — Shiki highlighting reference
+  - Paseo `file-explorer-pane.tsx` — context menu actions pattern
+
+  **QA Scenarios**:
+  ```
+  Scenario: Edit file in file tree and save
+    Tool: Playwright
+    Preconditions: Project with a text file
+    Steps:
+      1. Double-click a file in the file tree
+      2. Verify file enters edit mode (textarea replaces filename)
+      3. Modify content
+      4. Ctrl+Enter to save
+      5. Verify success indicator
+    Expected: File content updated on disk, tree refreshes
+    Evidence: .omo/evidence/task-9-edit-save.png
+
+  Scenario: Cancel file edit reverts changes
+    Tool: Playwright
+    Preconditions: File in edit mode
+    Steps:
+      1. Modify content in textarea
+      2. Click Cancel / press Escape
+      3. Re-open file
+    Expected: Original content preserved, edit mode exited
+    Evidence: .omo/evidence/task-9-edit-cancel.txt
+  ```
+
+---
+
+## Final Verification
+
+- [ ] F1. **Plan Compliance Audit** — `oracle`
+  Verify all Must Have features are implemented, Must NOT Have are absent.
+  Output: VERDICT
+
+- [ ] F2. **Code Quality** — `unspecified-high`
+  Run `pnpm -C apps/web build`, `pnpm -C apps/server build`, check for `as any`/`@ts-ignore`/console.log.
+  Output: VERDICT
+
+- [ ] F3. **Real Manual QA** — `unspecified-high` + `playwright`
+  Execute all QA scenarios from every task, capture evidence.
+  Output: Scenarios [N/N pass]
+
+- [ ] F4. **Scope Fidelity** — `deep`
+  Verify spec matches implementation, no scope creep.
+  Output: Tasks [N/N compliant]
+
+---
+
+## Commit Strategy
+
+- **1**: `feat(server): add whitespace param to git diff + write_file endpoint`
+- **2**: `feat(web): diff preferences hook, toolbar toggles, split layout`
+- **3**: `feat(web): inline diff comments with zustand store`
+- **4**: `feat(web): in-browser file editing in file tree`
+
+---
+
+## Success Criteria
+
+### Verification Commands
+```bash
+pnpm -C apps/web build     # Must pass
+pnpm -C apps/server build  # Must pass
+```
+
+### Final Checklist
+- [ ] Side-by-side diff renders correctly
+- [ ] Hide whitespace re-fetches with `-w`
+- [ ] Wrap lines toggles CSS
+- [ ] Expand/Collapse all toggles
+- [ ] Inline comments: create, read, update, delete
+- [ ] File editing: read, modify, save, cancel
+- [ ] All preferences survive page reload