Back off automatic remote control reconnects with jitter

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Back off automatic remote control reconnects with jitter

Why

Closed WebSocket connections previously triggered immediate reconnects, and successful handshakes reset backoff even when connections were short-lived.

What changed

• Delay automatic reconnects before token refresh or enrollment, and report Connecting while waiting.
• Use exponential backoff with jitter between half and all of the delay, starting at 5 seconds and capped at 30 seconds.
• Retain backoff across short-lived connections and reset it after a connection lasts at least 60 seconds.
• Interrupt the reconnect delay on shutdown, auth owner invalidation, or enable/disable changes, including an immediate disable/enable pair.

Testing

Add connection tests for delayed token refresh, backoff retention and reset, explicit re-enabling, and prompt shutdown. Update retry tests to check jitter bounds, saturation during sustained failures, and backoff retention after a successful handshake.