style: Apply code formatting with go fmt

- Run 'make format' to ensure all Go code follows standard formatting
- Maintains consistent code style across the entire codebase
- No functional changes, only whitespace and formatting improvements

internal/merger/merger.go

@@ -448,7 +448,7 @@ func (m *Merger) UpdateAircraft(sourceID string, aircraft *modes.Aircraft, signa
 
 	state.LastUpdate = timestamp
 	state.TotalMessages++
-	
+
 	// Persist to database if available and aircraft has position
 	if m.db != nil && aircraft.Latitude != 0 && aircraft.Longitude != 0 {
 		m.saveAircraftToDatabase(aircraft, sourceID, signal, timestamp)
@@ -1077,7 +1077,7 @@ func (m *Merger) validatePosition(aircraft *modes.Aircraft, state *AircraftState
 func (m *Merger) saveAircraftToDatabase(aircraft *modes.Aircraft, sourceID string, signal float64, timestamp time.Time) {
 	// Convert ICAO24 to hex string
 	icaoHex := fmt.Sprintf("%06X", aircraft.ICAO24)
-	
+
 	// Prepare database record
 	record := database.AircraftHistoryRecord{
 		ICAO:           icaoHex,
@@ -1087,7 +1087,7 @@ func (m *Merger) saveAircraftToDatabase(aircraft *modes.Aircraft, sourceID strin
 		SourceID:       sourceID,
 		SignalStrength: &signal,
 	}
-	
+
 	// Add optional fields if available
 	if aircraft.Altitude > 0 {
 		record.Altitude = &aircraft.Altitude
@@ -1107,7 +1107,7 @@ func (m *Merger) saveAircraftToDatabase(aircraft *modes.Aircraft, sourceID strin
 	if aircraft.Callsign != "" {
 		record.Callsign = &aircraft.Callsign
 	}
-	
+
 	// Save to database (non-blocking to avoid slowing down real-time processing)
 	go func() {
 		if err := m.db.GetHistoryManager().RecordAircraft(&record); err != nil {