emrg: GUI open-sessions sidebar + gui_state restore — P4 slice 2 (GUI multi-session rant P4)

[argszero]

Summary

P4 slice 2 of the GUI multi-session rant (2026-08-10T15:07:19): the open-sessions sidebar + boot restore — the other half of P4 after slice 1 (#637, open-sessions state + gui_state.json persistence).

Changes

emrg/gui/main.js

• restoreOpenSessions(sessions) — on init: read gui_state.json, re-open valid entries (cap 20, resume + re-subscribe), skip stale entries (removed + re-persisted), restore activeSid (fallback: most recent), window-title sync
• broadcastOpenSessions() — pushes open_sessions events to the renderer on every mutation (open/touch/activate/close/delete/new) — the sidebar's live data source
• init response now includes open_sessions + active_sid so the renderer adopts the restored active session without an extra switchSession IPC round-trip

emrg/gui/renderer

• sidebar.js — renderOpenSessions(list): cross-project open-session section at the top of the sidebar (项目名 / 会话标题, lastActive desc from main, active highlight, click → switch, right-click → close/rename/delete); highlight now also covers open-session items
• app.js — state.openSessions; handles open_sessions events; closeOpenSession(sid) (disconnect + remove container + keep disk data; closing the active session switches to the most recent remaining open session, else new); showOpenSessionsMenu (关闭保留数据 / rename / delete with confirm)
• index.html — #open-sessions nav + label above the conversation list
• i18n.js — zh/en: sidebar.openSessions / noOpenSessions / openSessionOf / app.closeSession / app.closeFailed
• layout.css — open-sessions section styling (bordered, max-height 40%, scrollable)

test/renderer.smoke.test.js — +4 tests (open_sessions event renders project/title + active highlight; close active session → switch to remaining + container released; close bg session → no switch; boot adopts restored activeSid). Mock upgrades: querySelectorAll DFS for class selectors (highlight), classList.toggle honors force (faithful DOM semantics). GUI 163→167 (renderer smoke 46→50); README/README.cn/Agent.md synced; 680 pytest green; node --check clean.

Verification

• GUI: 167 tests pass (43+17+22+50+15+7+3+3+7)
• Python: 680 pytest; doc-count guard passes
• node --check clean on all touched JS

[argszero]

✅ LGTM — cycle 20260810-180149 (author). P4 slice 2: open-sessions sidebar + gui_state restore; 167 GUI (163+4) + 680 pytest green.

[argszero]

✅ LGTM — cycle 20260810-181309. Reviewed the full diff: restoreOpenSessions (cap-20, stale-entry skip + re-persist, activeSid fallback, window-title sync), broadcastOpenSessions on all mutations, sidebar renderOpenSessions with active highlight + right-click menu (close-keep-data/rename/delete), busy-guard on closing the active session, zh/en i18n, bounded CSS. Verified locally: node --check clean; GUI 167/167 (163+4); pytest 680/680 incl. doc-count guard.

[pm25coder]

I tested this PR (P4 slice 2 — open-sessions sidebar + gui_state restore) end-to-end and the code review came back clean.

[argszero]

✅ LGTM — cycle 20260810-181428

Re-verified on head c8a4067: GUI suite 167/167 (renderer smoke 50 — open_sessions event renders project/title + active highlight; close active session switches to remaining + container released; close bg session keeps active pointer; boot adopts restored activeSid without switchSession round-trip; mock querySelectorAll DFS + classList.toggle force fidelity), 680 pytest green, doc-count guard passes (167 = 43+17+22+50+15+7+3+3+7), CLI OK, node --check clean.