Fix shutdown handling and optimize SQLite settings

- Fix Ctrl-C shutdown by using fx.Shutdowner instead of just canceling context
- Pass context from fx lifecycle to rw.Run() for proper cancellation
- Adjust WAL settings: checkpoint at 50MB, max size 100MB
- Reduce busy timeout from 30s to 2s to fail fast on lock contention

This should fix the issue where Ctrl-C doesn't cause shutdown and improve
database responsiveness under heavy load.

internal/database/database.go

@@ -91,19 +91,19 @@ func New(cfg *config.Config, logger *logger.Logger) (*Database, error) {
 func (d *Database) Initialize() error {
 	// Set SQLite pragmas for better performance
 	pragmas := []string{
-		"PRAGMA journal_mode=WAL",            // Write-Ahead Logging
-		"PRAGMA synchronous=OFF",             // Don't wait for disk writes
-		"PRAGMA cache_size=-2097152",         // 2GB cache (negative = KB)
-		"PRAGMA temp_store=MEMORY",           // Use memory for temp tables
-		"PRAGMA mmap_size=536870912",         // 512MB memory-mapped I/O
-		"PRAGMA wal_autocheckpoint=1000",     // Checkpoint every 1000 pages (4MB with 4KB pages)
-		"PRAGMA wal_checkpoint(PASSIVE)",     // Checkpoint now
-		"PRAGMA page_size=4096",              // Standard page size
-		"PRAGMA busy_timeout=30000",          // 30 second busy timeout
-		"PRAGMA locking_mode=NORMAL",         // Allow multiple connections
-		"PRAGMA read_uncommitted=true",       // Allow dirty reads for better concurrency
-		"PRAGMA journal_size_limit=67108864", // Limit WAL to 64MB
-		"PRAGMA analysis_limit=0",            // Disable automatic ANALYZE
+		"PRAGMA journal_mode=WAL",             // Write-Ahead Logging
+		"PRAGMA synchronous=OFF",              // Don't wait for disk writes
+		"PRAGMA cache_size=-2097152",          // 2GB cache (negative = KB)
+		"PRAGMA temp_store=MEMORY",            // Use memory for temp tables
+		"PRAGMA mmap_size=536870912",          // 512MB memory-mapped I/O
+		"PRAGMA wal_autocheckpoint=12500",     // Checkpoint every 12.5k pages (50MB with 4KB pages)
+		"PRAGMA wal_checkpoint(PASSIVE)",      // Checkpoint now
+		"PRAGMA page_size=4096",               // Standard page size
+		"PRAGMA busy_timeout=2000",            // 2 second busy timeout
+		"PRAGMA locking_mode=NORMAL",          // Allow multiple connections
+		"PRAGMA read_uncommitted=true",        // Allow dirty reads for better concurrency
+		"PRAGMA journal_size_limit=104857600", // Limit WAL to 100MB
+		"PRAGMA analysis_limit=0",             // Disable automatic ANALYZE
 	}
 
 	for _, pragma := range pragmas {