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).

src/routing_layer/topo_node.c

@@ -376,6 +376,7 @@ int topo_node_serialize(struct TOPO_NODE* ni, struct TOPO_GROUP_NODE* nq,
     msg.client_type     = ni->client_type;
     msg.client_activity = ni->client_activity;
     msg.cumulative_rtt   = cumulative_rtt;
+    if (nq->radio) msg.flags |= TOPO_FLAG_RADIO;
 
     size_t total = TOPOMSG_NODE_HDR_SIZE + (size_t)topo_node_dyn_size(&msg);
     if (total > out_max) return -1;
@@ -853,6 +854,7 @@ int topo_group_update_my_nodeinfo(struct UTUN_INSTANCE* instance, struct TOPO_GR
                    || (vc6 != (group->local_node->subnets ? topo_list_count((struct _topo_head*)group->local_node->subnets->v6_subnets) : 0))
                    || (oni->client_type != instance->client_type)
                    || (oni->client_activity != instance->client_activity)
+                   || (group->local_node->radio != group->radio_active)
                    || (memcmp(oni->ed25519_public_key, group->ed25519_public_key, SC_PUBKEY_SIZE) != 0);
         }
     }
@@ -879,6 +881,7 @@ int topo_group_update_my_nodeinfo(struct UTUN_INSTANCE* instance, struct TOPO_GR
         ni->ver       = (old_ver % 255) + 1;
         ni->client_type     = instance->client_type;
         ni->client_activity = instance->client_activity;
+        lq->radio = group->radio_active;
         memcpy(ni->public_key, instance->my_keys.public_key, SC_PUBKEY_SIZE);
         memcpy(ni->ed25519_public_key, group->ed25519_public_key, SC_PUBKEY_SIZE);
         if (name_len) { ni->node_name = u_malloc(name_len + 1); if (ni->node_name) { memcpy(ni->node_name, instance->name, name_len); ni->node_name[name_len] = 0; } }