Add archive relay query augmentation and access-based GC (v0.45.0)

- Add async archive relay querying (local results immediate, archives in background)
- Add query caching with filter normalization to avoid repeated requests
- Add session-deduplicated access tracking for events
- Add continuous garbage collection based on access patterns
- Auto-detect storage limit (80% of filesystem) when ORLY_MAX_STORAGE_BYTES=0
- Support NIP-50 search queries to archive relays

New environment variables:
- ORLY_ARCHIVE_ENABLED: Enable archive relay query augmentation
- ORLY_ARCHIVE_RELAYS: Comma-separated archive relay URLs
- ORLY_ARCHIVE_TIMEOUT_SEC: Archive query timeout
- ORLY_ARCHIVE_CACHE_TTL_HRS: Query deduplication window
- ORLY_GC_ENABLED: Enable access-based garbage collection
- ORLY_MAX_STORAGE_BYTES: Max storage (0=auto 80%)
- ORLY_GC_INTERVAL_SEC: GC check interval
- ORLY_GC_BATCH_SIZE: Events per GC cycle

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

cmd/benchmark/relysqlite_wrapper.go

@@ -278,6 +278,17 @@ func (w *RelySQLiteWrapper) EventIdsBySerial(start uint64, count int) (evs []uin
 	return nil, fmt.Errorf("not implemented")
 }
 
+// Access tracking stubs (not needed for benchmarking)
+func (w *RelySQLiteWrapper) RecordEventAccess(serial uint64, connectionID string) error {
+	return nil // No-op for benchmarking
+}
+func (w *RelySQLiteWrapper) GetEventAccessInfo(serial uint64) (lastAccess int64, accessCount uint32, err error) {
+	return 0, 0, nil
+}
+func (w *RelySQLiteWrapper) GetLeastAccessedEvents(limit int, minAgeSec int64) (serials []uint64, err error) {
+	return nil, nil
+}
+
 // Helper function to check if a kind is replaceable
 func isReplaceableKind(kind int) bool {
 	return (kind >= 10000 && kind < 20000) || kind == 0 || kind == 3