feat: group chat session lifecycle, typing recovery, mention highlighting (#186)

* feat: restore group chat system with Socket.IO and SQLite persistence

- GroupChatServer: Socket.IO server with room management, message history, typing indicators
- SQLite storage for rooms, messages, and agent configuration
- AgentClients: manages AI agent connections via socket.io-client, forwards @mentions to Hermes gateway
- REST API: room CRUD, agent management, invite codes
- Agent auto-restoration on server restart
- Tests for all REST endpoints

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* docs: add context-engine design document for group chat compression

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* fix: handle special-character session search

* fix: keep unicode dotted session search on quoted FTS path

* feat: add context engine and group chat frontend UI

- Context engine: three-zone compression (head/tail/summary) with LLM
  summarization, incremental updates, TTL cache, and graceful degradation
- Frontend: group chat page with Socket.IO client, room sidebar, message
  list, agent/member display, create/join-by-code modals
- Integration: wire context engine into agent-clients before /v1/runs
- Refactor ChatStorage to use global DB (getDb/ensureTable) with gc_ prefix
- Add i18n keys for group chat to all 8 locales
- Add sidebar nav entry and router for group chat page

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* fix: remove leftover main branch code from merge conflict resolution

The `isNumericQuery`, `hasUnsafeChars`, and `runLikeContentSearch` functions
no longer exist — they were replaced by HEAD's `shouldUseLiteralContentSearch`
and `runLiteralContentSearch`. This dead code block caused a TypeScript
compile error after the merge.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* fix: install missing socket.io dep and type ack params

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* fix: enable WebSocket proxy and fix socket.io transport for group chat

- Add ws: true to Vite proxy config so WebSocket upgrade requests
  are forwarded to the backend
- Allow both polling and websocket transports on server and client
  (polling as fallback when WebSocket upgrade fails through proxy)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* fix: separate socket.io path from REST routes for group chat

socket.io was mounted at /api/hermes/group-chat which intercepted all
REST requests to /api/hermes/group-chat/rooms etc, returning
"Transport unknown". Changed socket.io path to /api/hermes/group-chat/ws
to avoid conflicts.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* feat: improve group chat UI, agent management, and socket.io reliability

- Redesign GroupChatPanel with Naive UI, stacked agent avatars, and popover management
- Match GroupChatInput style with single chat input, add IME composition handling
- Add agent add/remove per room with profile selection and duplicate prevention
- Use @multiavatar for SVG avatar generation with caching
- Decouple joinRoom from socket.io, use REST API for data loading
- Switch socket.io to default path with /group-chat namespace to avoid proxy conflicts
- Restore agent connections after server is listening
- Add getRoomDetail REST endpoint and duplicate agent prevention (409)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* feat: server-side @mention routing with context compression status and queue

- Move @mention detection from agent socket listeners to server-side processMentions()
- Add per-room processing lock to block mention dispatch during compression
- Queue mentions during processing, drain only the latest when ready
- Emit context_status events (compressing/replying/ready) to room via Socket.IO
- Frontend displays compression status indicator above input
- Token-based compression trigger (100k threshold) with CJK-aware estimation
- Fix compressor type errors (countTokens parameter type)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* feat: improve group chat profile handling and session sync

Refine group chat room/session behavior with per-room compression controls, sidebar updates, and better stale session cleanup so multi-profile group chat state stays consistent.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* feat: group chat improvements — session lifecycle, typing recovery, mention highlighting

- Fix cross-profile session deletion with deferred delete queue
- Move saveSessionProfile to after gateway response confirmation
- Replace all console.log with logger in group-chat modules
- Add server-side typing/context_status state tracking for room rejoin
- Fix @ mention popup position to follow cursor
- Add @ mention highlighting (blue) in chat message content
- Fix mention regex to match all occurrences after HTML tags
- Enable esbuild minify and treeShaking
- Move @multiavatar/multiavatar to devDependencies
- Add i18n keys for group chat features
- Update tests for new functionality

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* chore: bump version to 0.4.5 and move @multiavatar to devDependencies

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
Co-authored-by: Zhicheng Han <zhicheng.han@mathematik.uni-goettingen.de>

packages/client/src/i18n/locales/ja.ts

@@ -48,6 +48,7 @@ export default {
     update: '更新',
     create: '作成',
     saveFailed: '保存に失敗しました',
+    deleteFailed: '削除に失敗しました',
     ok: 'OK',
     copied: 'コピーしました',
     copy: 'コピー',
@@ -76,6 +77,8 @@ export default {
     channels: 'チャンネル',
     terminal: 'ターミナル',
     files: 'ファイル',
+    groupChat: 'グループチャット',
+    groupConversation: '会話',
     settings: '設定',
     connected: '接続済み',
     disconnected: '未接続',
@@ -579,6 +582,55 @@ export default {
     saveFile: '保存',
   },
 
+  // グループチャット
+  groupChat: {
+    title: 'グループチャット',
+    createRoom: 'ルームを作成',
+    joinByCode: 'コードで参加',
+    roomName: 'ルーム名',
+    roomNamePlaceholder: 'ルーム名を入力',
+    inviteCode: '招待コード',
+    autoGenerate: '自動生成',
+    noRooms: 'ルームがありません',
+    selectOrCreate: 'ルームを選択または作成してチャットを開始',
+    agents: 'エージェント',
+    addAgent: 'エージェントを追加',
+    selectProfile: 'プロファイルを選択',
+    agentAdded: 'エージェントが追加されました',
+    agentAlreadyInRoom: 'このエージェントは既にルームにいます',
+    noAgents: 'このルームにエージェントはいません',
+    members: 'メンバー',
+    roomCreated: 'ルームが作成されました',
+    roomDeleted: 'ルームを削除しました',
+    deleteRoomConfirm: 'このルームを削除しますか？',
+    you: 'あなた',
+    joined: 'ルームに参加しました',
+    joinFailed: 'ルームへの参加に失敗しました',
+    inputPlaceholder: 'メッセージを入力... (Enterで送信)',
+    enterCode: '招待コードを入力',
+    yourName: 'あなたの名前',
+    yourNamePlaceholder: '表示名を入力',
+    yourDescription: '自己紹介（任意）',
+    yourDescriptionPlaceholder: '自分について教えてください...',
+    agentName: 'エージェント名',
+    agentNamePlaceholder: 'カスタム名（空欄ならプロファイル名）',
+    agentDesc: 'エージェントの説明',
+    agentDescPlaceholder: 'このエージェントの役割を説明...',
+    agentReplying: 'が返信中...',
+    agentCompressing: 'がコンテキストを圧縮中...',
+    compressionSettings: '圧縮設定',
+    triggerTokens: '圧縮トリガートークン数',
+    triggerTokensDesc: 'このトークン数を超えるとコンテキスト圧縮がトリガーされます',
+    maxHistoryTokens: '最大履歴トークン数',
+    maxHistoryTokensDesc: '圧縮後のLLM送信最大トークン数',
+    tailMessageCount: '末尾メッセージ数',
+    tailMessageCountDesc: '圧縮後にそのまま保持する最近のメッセージ数',
+    compressionConfig: '圧縮設定',
+    compressNow: '今すぐ圧縮',
+    compressingInProgress: '圧縮中です、お待ちください',
+    compressionSaved: '圧縮設定を保存しました',
+  },
+
   // ダウンロード
   download: {
     downloading: 'ダウンロード中...',