feat: right-click menus everywhere, workspace/session cost, long-term DB safety

Right-click menus: one portal shell (components/ContextMenu.tsx) for every
item with actions - sidebar/Recents/archived session rows (SessionMenu),
console tabs, pane headers, the Changes panel's files/tree/commits, the
workspace home, sessions outside a workspace (SessionRowMenu: Sessions
table, Dashboard, Activity, Workflow runs), prompt images, every Settings
list and every Claude Code/Codex config list (FileItemMenu). Buttons stay;
a delete keeps its button's confirm; the shell stops portal clicks from
reaching the card that opened it.

Status bar: Workspace $ and Session $ on the Workspace page, from
?lane= on GET /api/pricing/cost and the focused/replayed session's cost.

Database, no data dropped: synchronous=NORMAL, journal_size_limit 64 MB,
hourly PASSIVE checkpoint + PRAGMA optimize, idx_events_session_created
(replacing the redundant idx_events_session), watchdog reads
sessions.transcript_path, transcript parsed before the hook's write
transaction, GET /api/sessions/:id?events=0 for the web page (reloads only
on its own session, debounced), streamed export, transactional clear-data
and chunked cleanup, subagent import reads tool_use_ids once, runtime logs
rotated past 5 MB.

client/src/i18n/locales/en/sessions.json

@@ -40,5 +40,11 @@
     "transcriptNotFound": "Conversation transcript not found for this agent. The transcript file may be missing or not yet linked."
   },
   "remoteSourceBadgeTitle": "Collected from a remote machine",
-  "toolBadgeTitle": "Recorded by {{tool}}"
+  "toolBadgeTitle": "Recorded by {{tool}}",
+  "menu": {
+    "details": "Open session details",
+    "inWorkspace": "Open in its workspace",
+    "copyId": "Copy session ID",
+    "copyFolder": "Copy folder path"
+  }
 }