feat: Implement startup retry mechanism for custom stations and equalizer persistence

- Added state management for startup retry and custom station handling in `EstadoRadio`.
- Created tasks for implementing strict TDD with RED tests for HTTP failure retries and EQ persistence.
- Developed verification report to ensure compliance with TDD practices.
- Introduced fake services for testing, including `FakeServicioAudio`, `FakeServicioFavoritos`, and `FakeServicioRadio`.
- Implemented widget tests for `PantallaInicio` and `PantallaFavoritos` to validate UI behavior with custom stations.
- Enhanced `ServicioRadio` to support host rotation and retry logic for API calls.
- Established a new configuration file to enforce project constraints and testing rules.

lib/pantallas/pantalla_inicio.dart

@@ -146,7 +146,7 @@ class _PantallaInicioState extends State<PantallaInicio> {
   Widget _gridEmisoras(EstadoRadio estado, ThemeData theme) {
     final emisoras = _generoSeleccionado != null
         ? estado.resultadosBusqueda
-        : estado.populares;
+        : estado.emisorasInicio;
     final cargando = estado.cargandoPopulares ||
         (_generoSeleccionado != null && estado.cargandoBusqueda);