[FL-3600] Added fal_embedded parameter for PLUGIN apps (#3083)

* fbt, ufbt: added `fal_embedded` parameter for PLIGIN apps, to embed them into .fap
* fbt: fixed dependency settings for assets
* fbt: extapps: Removed unneeded casts
* fbt: extapps: code simplification
* fbt: fal_embedded: fixed dependency relations

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

scripts/fbt/appmanifest.py

@@ -79,11 +79,19 @@ class FlipperApplication:
     fap_extbuild: List[ExternallyBuiltFile] = field(default_factory=list)
     fap_private_libs: List[Library] = field(default_factory=list)
     fap_file_assets: Optional[str] = None
+    fal_embedded: bool = False
     # Internally used by fbt
     _appmanager: Optional["AppManager"] = None
     _appdir: Optional[object] = None
     _apppath: Optional[str] = None
     _plugins: List["FlipperApplication"] = field(default_factory=list)
+    _assets_dirs: List[object] = field(default_factory=list)
+    _section_fapmeta: Optional[object] = None
+    _section_fapfileassets: Optional[object] = None
+
+    @property
+    def embeds_plugins(self):
+        return any(plugin.fal_embedded for plugin in self._plugins)
 
     def supports_hardware_target(self, target: str):
         return target in self.targets or "all" in self.targets
@@ -137,6 +145,11 @@ class AppManager:
                 raise FlipperManifestException(
                     f"Plugin {kw.get('appid')} must have 'requires' in manifest"
                 )
+        else:
+            if kw.get("fal_embedded"):
+                raise FlipperManifestException(
+                    f"App {kw.get('appid')} cannot have fal_embedded set"
+                )
         # Harmless - cdefines for external apps are meaningless
         # if apptype == FlipperAppType.EXTERNAL and kw.get("cdefines"):
         #     raise FlipperManifestException(