UI pass: terminal color/clear, responsive headers, flat-document chat

[ANonABento]

What

Three things from the UI pass:

1. Terminal color + clear (fix(terminal))

The embedded tmux terminal had no color and clear/TUI redraws left artifacts. Root cause: the tmux attach client (whose output feeds xterm.js) was spawned with no TERM — on a GUI launch (TERM unset) tmux downgrades to a colorless dumb terminal and drops clear / alternate-screen sequences. Fixes in tmux_transport.rs:

• attach_in_pty: TERM=xterm-256color + COLORTERM=truecolor + -2
• ensure_tmux_server: explicit default-terminal tmux-256color + truecolor terminal-overrides
• create_session: COLORTERM in the session env

Takes effect on every attach, so existing sessions get color on reopen too.

2. Two-stage responsive headers (feat(panels))

Header controls overlapped at narrow panel widths. New useElementWidth + PanelDensityContext drive three tiers:

• regular (≥470px): tab labels + labelled runtime/Hold
• compact (360–470px): tabs → icons, runtime/Hold → icon buttons
• mini (<360px): tabs → icons; runtime + Hold + Kill fold into a generalized PanelOverflowMenu

PanelTabs gains a responsive prop; RuntimeModeToggle gains button|compact|menu variants; HoldButton extracted. Chef header gets the lighter pass (responsive tabs + Cmd+J hint hidden when tight).

3. Docs refresh (docs)

• ROADMAP.md — authoritative current state ranked for daily-driving
• specs/CHECKLIST_AS_ROADMAP.md — planned checklist /api + MCP tools
• CLAUDE.md known-gaps refreshed; STATUS.md MCP count 19 → 25

Verification

• tsc --noEmit, eslint, panel-tabs unit test, cargo check --workspace all green (precommit hooks enforce check + lint).
• Built the release bundle and relaunched; terminal color confirmed via the attach path.

Not included

• Chat rendering consolidation (agent transcript + chef bubbles → flat document) — next up.
• Perf pass (list virtualization, chunk splitting).

[ANonABento]

Added a third piece: flat-document chat consolidation (feat(chat)).

Chef chat used bubbles; the agent transcript used a flat left-border + role-label style. Unified both on the flat style (no bubbles) and shared the renderer:

• New chat-flat.tsx: ChatEntry (left accent border + role label + markdown body), ChatDivider, and ChatMarkdown — one GFM markdown renderer for every chat surface.
• chat-history.tsx (chef) rewritten off bubbles to flat entries (user='you', assistant='chef'); streaming/thinking/tools/queued preserved.
• agent-transcript.tsx drops its local markdown renderer for the shared ChatMarkdown (now GFM-enabled).

All 419 frontend tests pass (added a ResizeObserver mock + guard for jsdom/old webviews).

Still pending from the UI pass: agent-transcript visual polish (fully sharing ChatEntry) and the perf pass (list virtualization, chunk splitting).

[ANonABento]

Added the perf pass (perf: commit f7e445a) — completes the UI pass:

• Bundle split via vite manualChunks: react / xterm / markdown / motion / dnd pulled out of the single app chunk. Main chunk 1532 kB → 652 kB (gzip 429 → 172). shiki stays a lazy per-language async chunk.
• Memoized chef chat history so a streaming response no longer re-renders settled messages on every token.
• react-scan opt-in dev profiler (npm run profile or VITE_REACT_SCAN=1) — dev-only, dead-code-eliminated from production (verified absent from the prod bundle).
• eslint allowDefaultProject so vite.config.ts lints under the project service.

419 frontend tests green, tsc + lint clean.

Noted follow-ups (not in this PR): further code-splitting via React.lazy on heavy panels; the agent transcript rebuilds all items from events per streaming token (incremental build would help but is intricate); true list virtualization deferred (variable-height + collapsibles + auto-scroll make it high-risk).