[FL-1955] CLI RPC (#781)

- RPC: added CLI command to start session - all input bytes goes into RPC, all RPC output goes into VCP
- RPC: added command to close session (actually it only notifies transport layer)
- RPC: added recursive rmdir
- RPC: hard-coded listing for root directory (any, ext, int)
- Fixed CLI leak
- Fixed furi_record_delete leak
- Unit tests: repaired
- Unit tests: corrected output - remove excess, change dots with progress spinner
- Unit tests: added leak check
- Unit tests: SD mount check before start

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

applications/rpc/rpc_app.c

@@ -34,7 +34,7 @@ void rpc_system_app_start_process(const PB_Main* request, void* context) {
 
     furi_record_close("loader");
 
-    rpc_encode_and_send_empty(rpc, request->command_id, result);
+    rpc_send_and_release_empty(rpc, request->command_id, result);
 }
 
 void rpc_system_app_lock_status_process(const PB_Main* request, void* context) {
@@ -56,7 +56,8 @@ void rpc_system_app_lock_status_process(const PB_Main* request, void* context) {
 
     furi_record_close("loader");
 
-    rpc_encode_and_send(rpc, &response);
+    rpc_send_and_release(rpc, &response);
+    pb_release(&PB_Main_msg, &response);
 }
 
 void* rpc_system_app_alloc(Rpc* rpc) {