radio: PTT-радио в каналах (src/radio + chatgui + chatgui-android)

Новый модуль src/radio (radio/radio_audio/radio_headless) — push-to-talk
радио поверх topo-групп, доставка аудио в канал, headless-режим и тесты.
Интеграция в chatgui (ptt_hotkey_manager, radio_audio_engine, радионастройки,
вызовы) и chatgui-android (RadioAudioEngine, RadioOverlayService, UI).

tools/chatgui/src/settingsdialog.cpp

@@ -7,6 +7,7 @@
 #include "soundsettingspage.h"
 #include "audiodevicesettingspage.h"
 #include "storagesettingspage.h"
+#include "radiosettingspage.h"
 #include "connmonitorwindow.h"
 #include "../transport/gui_bridge.h"
 #include "../../lib/mem.h"
@@ -145,6 +146,9 @@ SettingsDialog::SettingsDialog(const QString& configPath, DbManager* db, UtunNod
     m_audioDevicePage = new AudioDeviceSettingsPage(db, recorder, m_pages);
     m_audioDevicePage->setConfigPath(m_configPath);
     m_pages->addWidget(m_audioDevicePage);
+
+    m_radioPage = new RadioSettingsPage(db, m_pages);
+    m_pages->addWidget(m_radioPage);
     rightLayout->addWidget(m_pages, 1);
 
     // --- Bottom buttons ---
@@ -289,6 +293,23 @@ void SettingsDialog::onSave() {
     m_soundPage->applyAndSave();
     m_audioDevicePage->applyAndSave();
     m_storagePage->applyAndSave();
+    m_radioPage->apply();
+
+    /* save radio PTT hotkeys to ui_state */
+    {
+        const char* key = "radio_ptt_hotkeys";
+        QByteArray val = m_radioPage->hotkeys().join('|').toUtf8();
+        size_t klen = strlen(key), vlen = (size_t)val.size();
+        size_t total = klen + 1 + vlen + 1;
+        if (total <= 256) {
+            struct save_ui_state_arg* arg = (struct save_ui_state_arg*)u_malloc(sizeof(struct save_ui_state_arg));
+            if (!arg) return;
+            arg->inst = gui_bridge_get_inst();
+            memcpy(arg->data, key, klen + 1);
+            memcpy(arg->data + klen + 1, val.constData(), vlen + 1);
+            gui_bridge_post_uasync_fn(chat_core_save_ui_state_trampoline, arg);
+        }
+    }
 
     /* save join_policy */
     {