0be35d257b
Previous logic caught 404 on heartbeat and re-registered, but the re- registration failed silently if the tracker wasn't fully ready yet. New approach: after any connection-refused streak, the heartbeat loop switches to re-registration mode and keeps retrying until the tracker accepts the registration (instead of sending heartbeats into a fresh registry that doesn't know this node). Falls back to the 404 path for the case where a node is purged without a full tracker restart. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>