fix(terminal): loading state, focus handling, debug logging

- Initialize loading=true in useTerminalSessions to prevent auto-create
  from firing before initial load completes
- Remove hasAutoCreated ref from TerminalPage (no longer needed)
- Add focus() to TerminalRef, call on tab switch
- Add term.focus() after term.open() in TerminalComponent
- Add console logging for WebSocket send/receive to debug no-i/o
- Revert backend _read_loop retry logic to original break-on-error

apps/web/src/hooks/use-terminal-sessions.ts

@@ -25,7 +25,7 @@ export function useTerminalSessions(
 ): UseTerminalSessionsResult {
 	const [sessions, setSessions] = useState<TerminalSession[]>([]);
 	const [activeSessionId, setActiveSessionId] = useState<string | null>(null);
-	const [loading, setLoading] = useState(false);
+	const [loading, setLoading] = useState(true);
 	const [error, setError] = useState<string | null>(null);
 
 	const loadSessions = useCallback(async () => {