[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/services/gui/application.fam

@@ -0,0 +1,36 @@
+App(
+    appid="gui",
+    name="GuiSrv",
+    apptype=FlipperAppType.SERVICE,
+    entry_point="gui_srv",
+    cdefines=["SRV_GUI"],
+    requires=[
+        "input",
+        "notification",
+    ],
+    stack_size=2 * 1024,
+    order=70,
+    sdk_headers=[
+        "gui.h",
+        "elements.h",
+        "view_dispatcher.h",
+        "view_stack.h",
+        "modules/button_menu.h",
+        "modules/byte_input.h",
+        "modules/popup.h",
+        "modules/text_input.h",
+        "modules/widget.h",
+        "modules/validators.h",
+        "modules/file_browser.h",
+        "modules/button_panel.h",
+        "modules/variable_item_list.h",
+        "modules/file_browser_worker.h",
+        "modules/menu.h",
+        "modules/dialog_ex.h",
+        "modules/loading.h",
+        "modules/text_box.h",
+        "modules/submenu.h",
+        "modules/widget_elements/widget_element.h",
+        "modules/empty_screen.h",
+    ],
+)