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>

pkg/database/interface.go

@@ -104,6 +104,16 @@ type Database interface {
 	CacheEvents(f *filter.F, events event.S)
 	InvalidateQueryCache()
 
+	// Access tracking for storage management (garbage collection based on access patterns)
+	// RecordEventAccess records an access to an event by a connection.
+	// The connectionID is used to deduplicate accesses from the same connection.
+	RecordEventAccess(serial uint64, connectionID string) error
+	// GetEventAccessInfo returns the last access time and access count for an event.
+	GetEventAccessInfo(serial uint64) (lastAccess int64, accessCount uint32, err error)
+	// GetLeastAccessedEvents returns event serials sorted by coldness (oldest/lowest access).
+	// limit: max events to return, minAgeSec: minimum age in seconds since last access.
+	GetLeastAccessedEvents(limit int, minAgeSec int64) (serials []uint64, err error)
+
 	// Utility methods
 	EventIdsBySerial(start uint64, count int) (evs []uint64, err error)
 }