[FL-2627] Flipper applications: SDK, build and debug system (#1387)

* Added support for running applications from SD card (FAPs - Flipper Application Packages)
* Added plugin_dist target for fbt to build FAPs
* All apps of type FlipperAppType.EXTERNAL and FlipperAppType.PLUGIN are built as FAPs by default
* Updated VSCode configuration for new fbt features - re-deploy stock configuration to use them
* Added debugging support for FAPs with fbt debug & VSCode
* Added public firmware API with automated versioning

Co-authored-by: hedger <hedger@users.noreply.github.com>
Co-authored-by: SG <who.just.the.doctor@gmail.com>
Co-authored-by: あく <alleteam@gmail.com>

applications/main/gpio/scenes/gpio_scene_test.c

@@ -0,0 +1,30 @@
+#include "../gpio_app_i.h"
+
+void gpio_scene_test_ok_callback(InputType type, void* context) {
+    furi_assert(context);
+    GpioApp* app = context;
+
+    if(type == InputTypePress) {
+        notification_message(app->notifications, &sequence_set_green_255);
+    } else if(type == InputTypeRelease) {
+        notification_message(app->notifications, &sequence_reset_green);
+    }
+}
+
+void gpio_scene_test_on_enter(void* context) {
+    GpioApp* app = context;
+    gpio_item_configure_all_pins(GpioModeOutputPushPull);
+    gpio_test_set_ok_callback(app->gpio_test, gpio_scene_test_ok_callback, app);
+    view_dispatcher_switch_to_view(app->view_dispatcher, GpioAppViewGpioTest);
+}
+
+bool gpio_scene_test_on_event(void* context, SceneManagerEvent event) {
+    UNUSED(context);
+    UNUSED(event);
+    return false;
+}
+
+void gpio_scene_test_on_exit(void* context) {
+    UNUSED(context);
+    gpio_item_configure_all_pins(GpioModeAnalog);
+}