tab-close + chat archive/delete + landing-card buttons + 1000px content cap

Feature 1 — Tab close menu (pure local pane state, no API):
- ChatTabBar context menu: Rename / sep / Close / Close others / Close to right / Close all
- Workspace bulk-tab primitives: closeOtherTabs, closeTabsToRight, closeAllTabs (manipulate panes[].chatIds, no fetch)
- Drop in-bar Delete; landing card's name-typed Delete is the canonical destructive path

Feature 2 — Chat archive + delete:
- chats.status vocabulary aligned with projects ('open' | 'archived'); DROP old inline CHECK, UPDATE 'closed' → 'archived', ADD new named chats_status_chk
- POST /api/chats/:id/archive (204) + POST /api/chats/:id/unarchive (200) + GET /api/sessions/:id/chats?status=archived; DELETE publishes chat_deleted; PATCH simplified to name-only
- 3 new WS frames: chat_archived, chat_unarchived, chat_deleted (renamed from chat_closed)
- Same dedup discipline: server-only publish, no local sessionEvents.emit in client
- SessionLandingPage: right-click ContextMenu (Open / Rename / Archive / sep / Delete-destructive), inline rename, archive confirm dialog, delete dialog with name-typed Input gated until typed text === chat.name, Archived chats collapsible section with Restore
- Card-level Archive + Delete icon buttons reusing the same dialog state setters; stopPropagation on both so card click still opens the chat; archived cards keep only Restore

UX — chat content width cap:
- ChatPane content (MessageList, queue chips, stop button, ChatInput) wrapped in inner max-w-[1000px] mx-auto w-full so messages center; outer border-t / scroll containers stay full-width so pane chrome and backgrounds remain edge-to-edge
- No new deps, no media queries (narrow viewports collapse to width naturally)

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

apps/web/src/api/client.ts

@@ -117,18 +117,24 @@ export const api = {
   },
 
   chats: {
-    listForSession: (sessionId: string) =>
-      request<Chat[]>(`/api/sessions/${sessionId}/chats`),
+    listForSession: (sessionId: string, params?: { status?: 'open' | 'archived' }) =>
+      request<Chat[]>(
+        `/api/sessions/${sessionId}/chats${params?.status ? `?status=${params.status}` : ''}`
+      ),
     create: (sessionId: string, body?: { name?: string }) =>
       request<Chat>(`/api/sessions/${sessionId}/chats`, {
         method: 'POST',
         body: JSON.stringify(body ?? {}),
       }),
-    update: (chatId: string, body: { name?: string; status?: 'open' | 'closed' }) =>
+    update: (chatId: string, body: { name: string }) =>
       request<Chat>(`/api/chats/${chatId}`, {
         method: 'PATCH',
         body: JSON.stringify(body),
       }),
+    archive: (chatId: string) =>
+      request<void>(`/api/chats/${chatId}/archive`, { method: 'POST' }),
+    unarchive: (chatId: string) =>
+      request<Chat>(`/api/chats/${chatId}/unarchive`, { method: 'POST' }),
     remove: (chatId: string) =>
       request<void>(`/api/chats/${chatId}`, { method: 'DELETE' }),
     messages: (chatId: string) =>