Feature/sliding freq (#3280)

* Add sliding-frequency audio receiver tuning
* Move ADS-B receiver to external app
* Move AIS receiver to external app
* Move APRS receiver to external app
* Move APRS transmitter to external app
* Isolate filtered spectrum collection from WFM
* Fixed the issues #3280
* fpga_bridge.c: init registers per reference fpga_init, add quarter-shift mode setter
* radio.hpp: expose cached FPGA quarter-rate shift
* radio.cpp: program FPGA quarter-rate shift together with tuning offset
* tuning.hpp: pass AFE rate and direction to tuning config, add quarter_shift field
* tuning.cpp: import full PRALINE RX/TX tuning tables with quarter-shift offsets
* clock_manager: stop writing bogus RX digital gain, keep quarter shift across rate changes
* receiver_model: port LPF bandwidth from reference auto_bandwidth, use cached quarter shift
* adsb_rx: enable RF amp by default on first run
* ui_geomap.hpp: add hemisphere fields, degrees become magnitude
* ui_geomap: use hemisphere selector for lat/lon sign, fix minute/second wrap carry
* ui_menu: guard select against empty menu
* waterfall_designer: header updates for profile file handling
* waterfall_designer: exception-free profile parsing, CRLF handling, deferred nav callbacks, backup cleanup
* external.ld: scope app section globs to their own object directories
* CMakeLists: relink when external.ld changes
* tools: add external app symbol placement checker
* tools: add guru meditation address lookup script
* tools: add per-function stack usage report script
Co-authored-by: gullradriel <gullradriel@users.noreply.github.com>

firmware/common/dsp_fir_taps.hpp

@@ -44,6 +44,111 @@ struct fir_taps_complex {
     std::array<complex16_t, N> taps;
 };
 
+/*
+ * 768kHz -> 384kHz half-band prefilter. The broad 80...304kHz
+ * transition makes this stage inexpensive while protecting the useful band.
+ */
+constexpr fir_taps_real<16> taps_audio_wide_halfband_0{
+    .low_frequency_normalized = -80000.0f / 768000.0f,
+    .high_frequency_normalized = 80000.0f / 768000.0f,
+    .transition_normalized = 224000.0f / 768000.0f,
+    .taps = {{
+        -171,
+        0,
+        1144,
+        0,
+        -4481,
+        0,
+        19892,
+        32767,
+        19892,
+        0,
+        -4481,
+        0,
+        1144,
+        0,
+        -171,
+        0,
+    }},
+};
+
+/*
+ * Spectrum capture anti-alias half-band filter. It is run only while a
+ * contiguous 256-sample FFT frame is being collected:
+ *   384kHz -> 192kHz (Zoom x1)
+ *   192kHz ->  96kHz (additional stage for Zoom x2)
+ */
+constexpr fir_taps_real<63> taps_audio_spectrum_halfband{
+    .low_frequency_normalized = -0.23f,
+    .high_frequency_normalized = 0.23f,
+    .transition_normalized = 0.04f,
+    .taps = {{
+        -15,
+        0,
+        37,
+        0,
+        -70,
+        0,
+        117,
+        0,
+        -184,
+        0,
+        274,
+        0,
+        -393,
+        0,
+        548,
+        0,
+        -751,
+        0,
+        1018,
+        0,
+        -1374,
+        0,
+        1872,
+        0,
+        -2622,
+        0,
+        3910,
+        0,
+        -6794,
+        0,
+        20812,
+        32767,
+        20812,
+        0,
+        -6794,
+        0,
+        3910,
+        0,
+        -2622,
+        0,
+        1872,
+        0,
+        -1374,
+        0,
+        1018,
+        0,
+        -751,
+        0,
+        548,
+        0,
+        -393,
+        0,
+        274,
+        0,
+        -184,
+        0,
+        117,
+        0,
+        -70,
+        0,
+        37,
+        0,
+        -16,
+    }},
+};
+
 // NBFM 16K0F3E emission type /////////////////////////////////////////////
 
 // IFIR image-reject filter: fs=3072000, pass=8000, stop=344000, decim=8, fout=384000

firmware/common/message.hpp

@@ -170,6 +170,7 @@ class Message {
         HunterStop = 112,
         TetraBsch = 113,
         TetraDnb = 114,
+        AudioDDCConfig = 115,
         MAX
     };
 
@@ -310,6 +311,16 @@ class SpectrumStreamingConfigMessage : public Message {
     Mode mode{Mode::Stopped};
 };
 
+class AudioDDCConfigMessage : public Message {
+   public:
+    constexpr AudioDDCConfigMessage(int32_t frequency)
+        : Message{ID::AudioDDCConfig},
+          frequency{frequency} {
+    }
+
+    int32_t frequency{0};
+};
+
 class WidebandSpectrumConfigMessage : public Message {
    public:
     constexpr WidebandSpectrumConfigMessage(
@@ -357,6 +368,7 @@ class AudioSpectrumMessage : public Message {
 struct ChannelSpectrum {
     std::array<uint8_t, 256> db{{0}};
     uint32_t sampling_rate{0};
+    int32_t channel_filter_offset{0};
     int32_t channel_filter_low_frequency{0};
     int32_t channel_filter_high_frequency{0};
     int32_t channel_filter_transition{0};