[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>

site_scons/site_tools/sconsmodular.py

@@ -40,10 +40,15 @@ def PhonyTarget(env, name, action, source=None, **kw):
     return command
 
 
+def ChangeFileExtension(env, fnode, ext):
+    return env.File(f"#{os.path.splitext(fnode.path)[0]}{ext}")
+
+
 def generate(env):
     env.AddMethod(BuildModule)
     env.AddMethod(BuildModules)
     env.AddMethod(PhonyTarget)
+    env.AddMethod(ChangeFileExtension)
 
 
 def exists(env):