feat(v0.3): O2 — resume past Claude sessions

- src/http/history.ts: listSessions() reads ~/.claude/projects/*/*.jsonl
  (mtime-sorted, top 50), parseSessionMeta() extracts cwd + first user prompt
  (pure, 4 unit tests); GET /sessions
- terminal-session: opts.initialInput (typed ~700ms after the shell is ready)
- tabs.newTabForResume(cwd,id): new tab in the project dir running
  'claude --resume <id>'
- public/history.ts: 🕘 panel listing sessions (project · time · preview) with
  Resume buttons
- Verified: /sessions returns 44 real sessions; panel lists project/time/preview.
  216 tests green.

src/server.ts

@@ -37,6 +37,7 @@ import { loadConfig } from './config.js'
 import { parseClientMessage, serialize } from './protocol.js'
 import { isOriginAllowed } from './http/origin.js'
 import { parseHookEvent } from './http/hook.js'
+import { listSessions } from './http/history.js'
 import { createSessionManager } from './session/manager.js'
 import { detachWs, writeInput, resize } from './session/session.js'
 import type { Config } from './types.js'
@@ -105,6 +106,11 @@ export function startServer(cfg: Config): { close(): Promise<void> } {
   const publicDir = path.join(__dirname, '..', 'public')
   app.use(express.static(publicDir))
 
+  // ── Claude Code history (O2) — list past sessions for the resume browser ──
+  app.get('/sessions', (_req, res) => {
+    res.json(listSessions(50))
+  })
+
   // ── Claude Code hook side-channel (H2) ────────────────────────────────────
   // Hooks running inside a spawned shell POST status here (loopback only — the
   // shell runs on the host). sessionId arrives in the X-Webterm-Session header.