Add historical flight track functionality

- Store track history with position, altitude, speed, and timestamp
- Automatic track point collection every 30 seconds when position changes
- API endpoint /api/aircraft/{hex}/history for individual aircraft tracks
- Frontend "Show History" button to display historical flight paths
- Click aircraft markers to show their historical track (dashed red line)
- Track cleanup: keep last 200 points per aircraft, 24-hour retention
- Add aircraft type badges in table view with color coding
- Start/end markers for historical tracks with timestamps

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

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

internal/server/server.go

@@ -61,6 +61,7 @@ func New(cfg *config.Config, staticFiles embed.FS, ctx context.Context) http.Han
 	
 	apiRouter := router.PathPrefix("/api").Subrouter()
 	apiRouter.HandleFunc("/aircraft", s.getAircraft).Methods("GET")
+	apiRouter.HandleFunc("/aircraft/{hex}/history", s.getAircraftHistory).Methods("GET")
 	apiRouter.HandleFunc("/stats", s.getStats).Methods("GET")
 	apiRouter.HandleFunc("/config", s.getConfig).Methods("GET")
 
@@ -122,6 +123,27 @@ func (s *Server) getStats(w http.ResponseWriter, r *http.Request) {
 	json.NewEncoder(w).Encode(stats)
 }
 
+func (s *Server) getAircraftHistory(w http.ResponseWriter, r *http.Request) {
+	vars := mux.Vars(r)
+	hex := vars["hex"]
+	
+	data := s.dump1090.GetAircraftData()
+	aircraft, exists := data.Aircraft[hex]
+	if !exists {
+		http.Error(w, "Aircraft not found", http.StatusNotFound)
+		return
+	}
+
+	response := map[string]interface{}{
+		"hex":          aircraft.Hex,
+		"flight":       aircraft.Flight,
+		"track_history": aircraft.TrackHistory,
+	}
+
+	w.Header().Set("Content-Type", "application/json")
+	json.NewEncoder(w).Encode(response)
+}
+
 func (s *Server) getConfig(w http.ResponseWriter, r *http.Request) {
 	configData := map[string]interface{}{
 		"origin": map[string]interface{}{