SSE connections previously created regular push consumers without durable
names. When browsers disconnected uncleanly or the API restarted, these
orphaned consumers persisted on the NATS server and continued draining
messages — each restart added more, eventually saturating the API at
100% CPU.
Switched to ordered_consumer=True which:
- Creates ephemeral consumers with no server-side ack state
- Auto-cleans on disconnect (no orphans)
- Still delivers new messages in real-time for SSE
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>