fix(rig-bridge): stop auth retry storm and rate-limit server log warnings

[ceotjoe]

Summary

• rig-bridge client (plugins/cloud-relay.js): on a 401/403 response, a new handleCredentialsInvalid() helper permanently stops both the push timer and the long-poll loop, logging once with a clear action for the user. Previously, pushState kept retrying every 2 s and longPollCommands retried every 1 s on any non-200 — flooding the server log at ~1 warn/s indefinitely.
• Server (server/routes/rig-bridge.js): requireRelayAuth now rate-limits logWarn to once per 5 minutes per sessionId. MeshCom ingest failure warnings are similarly throttled to once per minute per subtype.

Test plan

• Configure rig-bridge with a stale/wrong session token and confirm the server log shows only one auth warning, then silence for 5 minutes
• Confirm rig-bridge logs a single clear error message and stops retrying after receiving a 401
• Re-run Connect Cloud Relay in OHC Settings → Rig Bridge, confirm normal relay operation resumes with fresh credentials
• Verify no regression in normal relay auth (valid credentials still pass through)

🤖 Generated with Claude Code

[accius]

Couple of small things noticed during review, neither blocking, both are follow-up-able whenever you feel like it:

The authWarnLastLogged map keys on sessionId prefix but never clears stale entries. If a misbehaving client (or a deliberate one) cycles through a lot of bad sessionIds, that map slowly grows. The relayPollCountByIP cleanup pass that runs every 5 minutes a few lines up could probably absorb this one with a small tweak.

The other one is just messaging. The error tells the user to "re-run Connect Cloud Relay in OHC Settings" but in practice they also need to restart rig-bridge for the new credentials to actually take effect, since the old token is still in memory and credentialsInvalid stays set for the life of the process. Maybe worth adding "and restart rig-bridge" to that string so people don't bounce back wondering why it's still broken after clicking the button.