chore: maintenance — dependency majors, rename step 4, member Claude config, OpenAPI coverage

Dependencies
- Security: body-parser and multer DoS advisories fixed (npm audit: 0).
- Server: Express 5 (query parser kept "extended", req.body defaults to {},
  SPA catch-all /{*splat}, send-file helper restores Express 4's dot-folder
  rule for sendFile/download, alerts ack route without inline regex),
  better-sqlite3 13, js-yaml 5 (server/lib/yaml.js keeps js-yaml 4's default
  schema), uuid dropped for crypto.randomUUID, node-pty beta.18, multer 2.5.
- Client: React 19, xterm 6 (WebGL renderer replaces the removed canvas one,
  DOM fallback on context loss; Alt+arrow word moves re-mapped), lucide-react 1,
  TypeScript 7, i18next/react-i18next/codemirror minors.

Workspace rename step 4
- `agenthub lanes` and `--lane` exit 1 with "renamed: use …"; client api.ts,
  the CLI and the MCP server call /api/workspaces; /api/lanes stays mounted.

Server mode (S3): members manage their own Claude Code config
- server/lib/cc-target.js resolves whose config a /cc-config request touches
  and gates the router by allowlist; /profiles* and /plugins/update-all stay
  admin-only. Member writes go through write-as, CLI calls through sudo as the
  member (never -y), reads through openSafe; cc_config_changed reaches only
  its owner. Not verified live on an S3 install yet.

Other
- Chat: an HTML file is an artifact only when written whole and not a project
  page (index.html, or under src/, public/, templates/, …).
- OpenAPI covers every /api route; openapi-coverage.test.js guards it.
- read-pool test keeps its event loop alive (its worker is unref'd).
- Docs: plan statuses, checklists, CLI.md, LANES.md, SERVER-MODE.md, API.md.

client/src/hooks/useWebSocket.ts

@@ -63,7 +63,7 @@ type MessageHandler = (msg: WSMessage) => void;
  * auto-reconnects with capped exponential backoff on close - plus an
  * immediate reconnect attempt on tab focus/network-online/visibility-change
  * so the socket recovers quickly after a server restart or laptop sleep.
- * Guards against React 18 StrictMode's mount→cleanup→remount cycle opening a
+ * Guards against React StrictMode's mount→cleanup→remount cycle opening a
  * duplicate socket (see the inline comment in `connect`).
  * @param onMessage Called with every message parsed from the socket; the
  *   latest reference is used even across reconnects (no stale closures).
@@ -73,7 +73,7 @@ export function useWebSocket(onMessage: MessageHandler) {
   const wsRef = useRef<WebSocket | null>(null);
   const handlersRef = useRef<MessageHandler>(onMessage);
   const [connected, setConnected] = useState(false);
-  const reconnectTimer = useRef<ReturnType<typeof setTimeout>>();
+  const reconnectTimer = useRef<ReturnType<typeof setTimeout> | undefined>(undefined);
   const mountedRef = useRef(true);
   const reconnectAttempts = useRef(0);
 
@@ -82,7 +82,7 @@ export function useWebSocket(onMessage: MessageHandler) {
   const connect = useCallback(() => {
     if (!mountedRef.current) return;
     // Don't open a second socket if one is already alive or in flight.
-    // Without this, React 18 StrictMode (mount → cleanup → remount in dev)
+    // Without this, React StrictMode (mount → cleanup → remount in dev)
     // and the close→reconnect race could leave two sockets connected at the
     // same time. Both would receive every server broadcast, producing
     // duplicate stream_event deltas (doubled text, duplicate assistant