Made UniRFRemix a FAP, added a Loader for Main Menu

Requires one change in api_symbols.scv

applications/plugins/unirfremix/application.fam

@@ -0,0 +1,13 @@
+App(
+    appid="SubGHz_Remote",
+    name="Sub-GHz Remote",
+    apptype=FlipperAppType.EXTERNAL,
+    entry_point="unirfremix_app",
+    cdefines=["APP_UNIRFREMIX"],
+    requires=["storage", "gui", "dialogs", "subghz"],
+    icon="A_UniRFRemix_14",
+    stack_size=4 * 1024,
+    order=11,
+    fap_icon="unirfIcon.png",
+    fap_category="Main",
+)