fix(theming): Document correct response schema if app is not enabled

apps/theming/lib/Controller/ThemingController.php

@@ -429,7 +429,7 @@ public function getThemeStylesheet(string $themeId, bool $plain = false, bool $w
 	 *
 	 * @param string $app ID of the app
 	 * @psalm-suppress LessSpecificReturnStatement The content of the Manifest doesn't need to be described in the return type
-	 * @return JSONResponse<Http::STATUS_OK, array{name: string, short_name: string, start_url: string, theme_color: string, background_color: string, description: string, icons: list<array{src: non-empty-string, type: string, sizes: string}>, display_override: list<string>, display: string}, array{}>|JSONResponse<Http::STATUS_NOT_FOUND, array{}, array{}>
+	 * @return JSONResponse<Http::STATUS_OK, array{name: string, short_name: string, start_url: string, theme_color: string, background_color: string, description: string, icons: list<array{src: non-empty-string, type: string, sizes: string}>, display_override: list<string>, display: string}, array{}>|JSONResponse<Http::STATUS_NOT_FOUND, list<empty>, array{}>
 	 *
 	 * 200: Manifest returned
 	 * 404: App not found

apps/theming/openapi.json

@@ -410,9 +410,7 @@
                         "description": "App not found",
                         "content": {
                             "application/json": {
-                                "schema": {
-                                    "type": "object"
-                                }
+                                "schema": {}
                             }
                         }
                     }

openapi.json

@@ -28042,9 +28042,7 @@
                         "description": "App not found",
                         "content": {
                             "application/json": {
-                                "schema": {
-                                    "type": "object"
-                                }
+                                "schema": {}
                             }
                         }
                     }