[FL-1721] Bluetooth refactoring (#747)

* ble-glue: add on connect \ disconnect, on send \ received callbacks
* bt: rework service with furi-hal-bt and callbacks
* bt: update battery level on connect
* ble-glue: set one callback with parameters
* bt: rework callbacks, remove unused API
* ble-glue: remove dead code
* furi-hal-bt: add documentation
* ble-glue: apply changes for f7 target
* bt: rename RpcInstance -> Rpc
* ble: add disconnection reason
* ble: don't open bt record from GAP
* bt: fix RPC session close
* Assets: separate targets for icons and protobuf

Co-authored-by: あく <alleteam@gmail.com>

firmware/targets/f7/ble-glue/gap.h

@@ -1,11 +1,31 @@
 #pragma once
 
+#include <stdint.h>
 #include <stdbool.h>
 
 #ifdef __cplusplus
 extern "C" {
 #endif
 
+typedef enum {
+    BleEventTypeConnected,
+    BleEventTypeDisconnected,
+    BleEventTypeStartAdvertising,
+    BleEventTypeStopAdvertising,
+    BleEventTypePinCodeShow,
+} BleEventType;
+
+typedef union {
+    uint32_t pin_code;
+} BleEventData;
+
+typedef struct {
+    BleEventType type;
+    BleEventData data;
+} BleEvent;
+
+typedef void(*BleEventCallback) (BleEvent event, void* context);
+
 typedef enum {
     GapStateIdle,
     GapStateAdvFast,
@@ -13,7 +33,7 @@ typedef enum {
     GapStateConnected,
 } GapState;
 
-bool gap_init();
+bool gap_init(BleEventCallback on_event_cb, void* context);
 
 void gap_start_advertising();