fix: stabilize tests and refine RBAC model for privileged roles

- Updated devfront to recognize 'rp_admin' and 'tenant_admin' as privileged developer roles.
- Added specific forbidden messages for privileged roles in devfront.
- Improved adminfront Worksmobile test reliability across browsers.
- Updated Makefile to skip userfront tests in environments without Flutter SDK.
- Applied lint and format fixes across adminfront and devfront.

devfront/src/features/developer-request/DeveloperRequestPage.test.tsx

@@ -1,6 +1,6 @@
-import { act } from "react-dom/test-utils";
-import { createRoot, type Root } from "react-dom/client";
 import { QueryClient, QueryClientProvider } from "@tanstack/react-query";
+import { createRoot, type Root } from "react-dom/client";
+import { act } from "react-dom/test-utils";
 import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
 import DeveloperRequestPage from "./DeveloperRequestPage";