Looking glass beep (#2036)

* first draft of looking beep
* fixed beep squelch range in percent
* took out steps 
* gui adjustements
* uniformize calculation and beep squelch in db
* uniformisation, fix 24/48 error

firmware/baseband/proc_wideband_spectrum.hpp

@@ -43,6 +43,9 @@ class WidebandSpectrum : public BasebandProcessor {
     bool configured = false;
     size_t baseband_fs = 20000000;
 
+    void on_beep_message(const AudioBeepMessage& message);
+    void on_signal_message(const RequestSignalMessage& message);
+
     SpectrumCollector channel_spectrum{};
 
     std::array<complex16_t, 256> spectrum{};