Add automatic WebSocket reconnection with exponential backoff

[EhabY]

WebSocket streams occasionally drop due to client network loss or server-side interruptions. Today, many parts of the app rely on one-way WebSockets for push updates, and a closed socket isn’t re-established unless the user refreshes the window. This leads to stale UIs (e.g., the agent metadata status bar showing an unknown error) until a manual reload.

2025-09-25 17:27:02.604 [warning] Failed to query metadata: WebSocket closed unexpectedly: undefined undefined

Proposal:
Introduce an automatic reconnection policy for all one-way WebSocket clients:

• Reconnect with exponential backoff + jitter, capped (e.g., 250ms → 1s → 2s … up to 30s).
• Stop retrying on non-recoverable close codes (auth errors, 4xx) and surface a clear message.
• Resume prior subscriptions/state on reconnect; reset backoff after stable activity.
• Log reconnection attempts.

Expected outcome:
Sockets recover transparently from transient failures; users don’t need to refresh to restore live updates.