feat(v0.3): H4 — live Claude status badge + notifications + setup-hooks

- terminal-session: handle 'status' frame → claudeStatus + onClaudeStatus
- tabs: per-tab Claude glyph (⚙ working / ⏳ waiting / ✓ idle); inactive
  'waiting' tab gets an amber highlight + a browser notification (permission
  requested on first tab switch)
- scripts/setup-hooks.mjs + 'npm run setup-hooks': idempotently install/remove
  command hooks in ~/.claude/settings.json (inline curl to $WEBTERM_HOOK_URL with
  $WEBTERM_SESSION; no-op outside web-terminal); backs up settings.json
- Browser-verified end-to-end: PermissionRequest→⏳, PreToolUse→⚙, Stop→✓;
  inactive waiting tab shows amber + glyph. 205 tests green.

package.json

@@ -16,7 +16,8 @@
     "dev:web": "esbuild public/main.ts --bundle --format=esm --outdir=public/build --sourcemap --watch",
     "typecheck": "tsc -p tsconfig.json --noEmit && tsc -p tsconfig.web.json",
     "test": "vitest run",
-    "test:watch": "vitest"
+    "test:watch": "vitest",
+    "setup-hooks": "node scripts/setup-hooks.mjs"
   },
   "dependencies": {
     "@xterm/addon-fit": "^0.11.0",