Replaces wasteful 30s polling with event-driven design:
- No polling - worker sleeps until woken by SignalReplication()
- Replication triggers immediately on write operations
- Perfect for low-change vaults (could be days without writes)
Changes:
- edition/replication.go: Event-driven worker with channel signaling
- edition/edition.go: Add SignalReplication var
- edition/community.go: No-op SignalReplication stub
- edition/commercial.go: Wire up signalReplication
Architecture:
1. Write handler marks entry dirty (replication_dirty = 1)
2. Calls edition.SignalReplication() (non-blocking)
3. Worker wakes, batches ALL dirty entries
4. POSTs to backup POP
5. Clears dirty flags on success
6. Worker sleeps until next signal
Retry logic:
- Exponential backoff: 1s, 5s, 25s, 125s...
- Max 5 retries, then operator alert
- Dirty entries persist in DB until replicated
Resource efficiency:
- CPU: Only wakes on actual writes (not 2,880x/day polling)
- Network: Only sends when data changes
- For 10 writes/day: ~288x fewer wakeups than polling
Documentation:
- SPEC-replication-async.md: Full event-driven design spec
James