try gitea actions for dart server

Signed-off-by: Peter Siegmund <developer@mars3142.org>

server/cinema/lib/feature/middlewares/cors.dart

@@ -0,0 +1,24 @@
+import 'package:shelf/shelf.dart';
+
+Middleware cors() {
+  const corsHeaders = {
+    'Access-Control-Allow-Origin': '*',
+    'Access-Control-Allow-Methods': 'GET, POST, PUT, DELETE',
+    'Access-Control-Allow-Headers': 'Origin, Content-Type',
+    'Access-Control-Max-Age': "600",
+  };
+
+  return createMiddleware(
+    requestHandler: (Request request) {
+      if (request.method == "OPTIONS") {
+        return Response.ok('', headers: corsHeaders);
+      }
+      return null;
+    },
+    responseHandler: (Response response) {
+      final headers = Map<String, String>.from(response.headers);
+      headers.addEntries(corsHeaders.entries.map((e) => MapEntry(e.key, e.value)));
+      return response.change(headers: headers);
+    },
+  );
+}