feat: BooCode 2.0 UI — Ember theme, brand banner, coder tabs, model-attribution chips

- Ember theme (Obsidian charcoal + #ff7a18 orange), now DEFAULT_THEME_ID; server theme_id whitelist gains 'ember'
- Brand banner: transparent Westie mascot + >_BooCode wordmark, big/edge-to-edge (flood-filled to transparency + cropped)
- Coder panes are multi-tab: + opens a BooCode tab, split opens a pane (shared ChatTabBar via tabKind + createCoderTab; closeOtherTabs/tab-numbering extended to coder)
- Model-attribution: new messages.model column stamped at finalizeCompletion (BooChat/native coder) + dispatcher assistant-row creation (external coder); surfaced via view + wire types + live frame; rendered as a subtle shortened-name chip (shortenModelName)
- Composer Web toggle moved into a boxed focus-ringed input; glowing accent dot on tool rows
- Claude SDK follow-ups (1M context, follow-up-message fix, collapsed thinking/tool chips) + CLAUDE_SDK_BACKEND=1

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

CHANGELOG.md

@@ -2,6 +2,10 @@
 
 All notable changes per release tag. Most recent on top, ordered by tag creation date (which matches the git history). Tag names follow `vMAJOR.MINOR.PATCH-slug` — the slug describes what shipped, so the tag name alone is enough to recall the batch.
 
+## v2.7.8-ember-coder-tabs-model-chips — 2026-06-01
+
+The BooCode 2.0 visual identity plus two workflow features. **Ember theme** (`styles/themes/ember.css`, now `DEFAULT_THEME_ID`) is the signature orange-on-near-black look — rebuilt on Obsidian's flat charcoal structure (`#0c0c0e`/`#15151a`/`#1f1f23`) with `#ff7a18` swapped in for the purple, after a Reinvented-direction detour (neon borders + a scanline/glow texture overlay) was dialed back to taste; the server `theme_id` whitelist gains `ember` so it can actually be selected. The **brand banner** (`ProjectSidebar`) shows the eye-patch Westie mascot + the `>_BooCode` wordmark big and edge-to-edge on transparent backgrounds — the source PNGs shipped with baked-white canvases, so they were flood-filled to transparency from the corners (preserving the white dog, which a naive white-key would have destroyed) and cropped to bounds. **Coder panes are now multi-tab**: `+` opens a new BooCode tab (a fresh chat = a new agent context sharing the session worktree) while the split button still opens a pane — coder panes reuse the shared `ChatTabBar` via a kind-aware `tabKind`, backed by a new `createCoderTab` action with `closeOtherTabs`/tab-numbering extended to coder kind. **Model-attribution chips**: a new `messages.model` column (both apps share the table) stamped at `finalizeCompletion` (BooChat + native coder) and at the dispatcher's assistant-row creation (external coder), surfaced through the `messages_with_parts` view + wire types + the live `message_complete` frame (the Zod already allowed `model`; nothing consumed it), and rendered as a subtle accent chip with a shortened label (`shortenModelName` → `Sonnet 4.6`, `Qwen3.6 35B`) beside the message stats — so swapping models mid-coder-session stays legible. Also the composer moved its Web toggle into a boxed, focus-ringed input, tool rows lead with a glowing accent dot, and the Claude-SDK-backend follow-ups validated live this session (1M context window, follow-up-message fix, collapsed thinking/tool chips) land with `CLAUDE_SDK_BACKEND=1` flipped on. One snag fixed mid-deploy: the view's new `m.model` was first inserted mid-list and `CREATE OR REPLACE VIEW` can't reorder columns (42P16) — appended at the end. Web tsc + server + coder builds green; deployed (docker + boocoder, tools:34). Builds on `v2.7.7-pane-header-actions`.
+
 ## v2.7.7-pane-header-actions — 2026-06-01
 
 In-flight workspace UX work, committed alongside the v2.7 review batches. Extracts a shared `PaneHeaderActions` cluster (the +/Split/Reopen-closed-pane/Session-history/Close controls) used across the `ChatTabBar` and the desktop coder + terminal pane headers in `Workspace`, replacing the divergent per-header copies, with `SessionLandingPage` history enhancements and `useWorkspacePanes` tweaks. Also fixes a coder-side correctness bug: `resolveChatId` (`apps/coder/src/routes/chat-resolve.ts`) still read `sessions.workspace_panes` as a bare `WorkspacePane[]`, but `v2.6.5-panes-tabs-composer` widened it to a `WorkspaceState` envelope — so it mis-read the panes and, worse, clobbered `tabNumbers`/`nextTabNumber`/`closedPaneStack` back to a bare array on every pane-chat write; a new `normalizeWorkspaceState` accepts either shape and preserves the envelope (with a regression test). Plus a CLAUDE.md doc-sync (apps/coder vitest suite, deploy-by-surface, dual-remote push, in-flight-web-WIP staging, release-branch naming). Web tsc + coder build + coder tests green. Builds on `v2.7.6-agent-status-normalize`.