[FL-2675] /int space reservation (#1448)

* storage: added global #defines for /int, /ext & /any
* storage: introduced PATH_EXT, PATH_INT& PATH_ANY macros
* core apps: moved hardcoded config files names to separate headers; prefixed them with "."; updater: added file name migration to new naming convention on backup extraction
* storage: fixed storage_merge_recursive handling of complex directory structures; storage_move_to_sd: changed data migration logic to all non-dot files & all folders
* core: added macro aliases for core record names
* Bumped protobuf commit pointer
* storage: reserved 5 pages in /int; denying write&creation of non-dot files when running out of free space

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

applications/snake_game/snake_game.c

@@ -304,7 +304,7 @@ int32_t snake_game_app(void* p) {
     furi_timer_start(timer, furi_kernel_get_tick_frequency() / 4);
 
     // Open GUI and register view_port
-    Gui* gui = furi_record_open("gui");
+    Gui* gui = furi_record_open(RECORD_GUI);
     gui_add_view_port(gui, view_port, GuiLayerFullscreen);
 
     SnakeEvent event;
@@ -354,7 +354,7 @@ int32_t snake_game_app(void* p) {
     furi_timer_free(timer);
     view_port_enabled_set(view_port, false);
     gui_remove_view_port(gui, view_port);
-    furi_record_close("gui");
+    furi_record_close(RECORD_GUI);
     view_port_free(view_port);
     furi_message_queue_free(event_queue);
     delete_mutex(&state_mutex);