chore(openspec): drop 9 superseded proposals + 11 stub archive files

Drop 9 batch proposals that are superseded by the boocode-lift-analysis
(boocontext-audit, conductor upgrades, self-healing/verify-gate skills):
add-3tier-memory, import-llm-evaluator, import-pregel-engine, plugin-platform,
conductor-evolution, code-intelligence-upgrade, dev-workflow, ui-overhaul,
agent-reliability.

Delete 11 stub archive files (49-66B each, 'Status: Shipped. Archived.' only)
that provide zero documentation value over the existing CHANGELOG.md + git tags.

openspec/changes/enhanced-file-panel/design.md

@@ -0,0 +1,64 @@
+# Enhanced File Panel — Design Decisions
+
+## D1: Diff preference system
+
+A `useDiffPreferences` hook manages three stored preferences:
+
+```typescript
+interface DiffPreferences {
+  layout: 'unified' | 'split';    // default: 'unified'
+  wrapLines: boolean;              // default: false
+  hideWhitespace: boolean;         // default: false
+}
+```
+
+Persisted via localStorage key `boocode.diff.preferences`.
+**Reference**: `/opt/forks/paseo/hooks/use-changes-preferences/storage.ts`
+
+## D2: Side-by-side diff layout
+
+Split layout renders two columns (left = removals, right = additions) with aligned line numbers.
+
+Algorithm (adapted from Paseo `diff-layout.ts` `buildSplitDiffRows`):
+1. Parse unified diff into hunks (reuse existing `splitDiffByFile`)
+2. Group remove lines into pendingRemovals, add lines into pendingAdditions
+3. Flush paired rows when encountering context lines
+4. Unpaired lines get an empty cell on one side
+
+## D3: Hide whitespace (server-side)
+
+`GET /api/projects/:id/git/diff` gains optional `whitespace=1` query param.
+When set, `git diff` appends `-w` (`--ignore-all-space`).
+
+## D4: Wrap lines (CSS-only)
+
+When `wrapLines` is true: `white-space: pre-wrap; overflow-wrap: anywhere`
+replaces `white-space: pre; overflow-x: auto`. Gutter stays unwrapped.
+
+## D5: Expand/Collapse all
+
+`allExpanded` computed as `files.every(f => expandedPaths.has(f.path))`.
+Toggle button adds all paths to expandedPaths or clears them.
+
+## D6: Inline diff comments
+
+Data model:
+```typescript
+interface DiffComment {
+  id: string; filePath: string; side: 'old' | 'new';
+  lineNumber: number; body: string;
+  createdAt: number; updatedAt: number;
+}
+```
+
+Zustand store with localStorage persistence, keyed by `${sessionId}:${mode}`.
+
+## D7: File editing
+
+Double-click file in tree → fetch content via `view_file` → textarea →
+Save calls `POST /api/projects/:id/write_file` → triggers `git_diff_refresh`.
+Path validated via existing `pathGuard`.
+
+## D8: No DB / no WS frames / no contract changes
+
+All new state is client-side (localStorage, React state, Zustand).