Refactor RF Configuration Management (#2245)

- Introduced RFConfiguration class to encapsulate RF settings and operations.
- Replaced direct usage of RFConfig structure with iRFConfig instance across multiple files.
- Updated frequency handling in actuatorSomfy, gatewayPilight, gatewayRF, and gatewayRF2 to use iRFConfig.
- Modified webUI to interact with iRFConfig for RF settings management.
- Removed deprecated RFConfig structure and related functions.
- Enhanced JSON handling for RF configuration loading and saving.
- Improved logging for RF configuration operations.

main/rf/RFReceiver.h

@@ -0,0 +1,15 @@
+#ifndef RFRECEIVER_H
+#define RFRECEIVER_H
+#pragma once
+
+class RFReceiver {
+public:
+  virtual ~RFReceiver() = default;
+
+  // Pure virtual methods
+  virtual void enable() = 0;
+  virtual void disable() = 0;
+  virtual int getReceiverID() const = 0;
+};
+
+#endif // RFRECEIVER_H