Remote comms: Basic Rate Limiting

[sirtimid]

Implement simple per-peer rate limiting to prevent basic abuse scenarios. Track message count per peer with a sliding window of 1 second, limiting to 100 messages per second. For connection attempts, limit to 10 attempts per minute per peer. When limits are exceeded, queue messages up to the queue limit, then drop new messages with an error log. This prevents both accidental and intentional flooding.