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/lib/api.ts

@@ -737,13 +737,15 @@ export const api = {
      * @param id The session id.
      * @returns `{ session, agents, events, workflows }` for the detail view.
      */
-    get: (id: string) =>
+    /** `events: false` sends `?events=0`: `events` comes back empty instead of
+     *  every event of the session with its full payload. */
+    get: (id: string, opts: { events?: boolean } = {}) =>
       request<{
         session: Session;
         agents: Agent[];
         events: DashboardEvent[];
         workflows: WorkflowRun[];
-      }>(`/sessions/${encodeURIComponent(id)}`),
+      }>(`/sessions/${encodeURIComponent(id)}${opts.events === false ? "?events=0" : ""}`),
     /**
      * GET /api/sessions/:id/stats - per-session rollups for the detail page.
      *
@@ -1334,11 +1336,13 @@ export const api = {
      *
      * @returns {@link CostResult} — the aggregate cost breakdown across sessions.
      */
-    totalCost: () => {
+    totalCost: (opts: { lane?: number } = {}) => {
       // Scope the aggregate to the active data-scope, exactly like the sessions /
       // stats / analytics endpoints — otherwise switching the Data scope selector
       // left the Dashboard "total cost" showing the un-narrowed global total.
+      // `lane`: only the sessions that workspace owns.
       const qs = new URLSearchParams({ tz_offset: String(new Date().getTimezoneOffset()) });
+      if (opts.lane !== undefined) qs.set("lane", String(opts.lane));
       applyScope(qs);
       return request<CostResult>(`/pricing/cost?${qs.toString()}`);
     },