harden admin api authorization and add authz regression tests

apps/admin/src/middleware.ts

@@ -25,14 +25,6 @@ const isPublicRoute = createRouteMatcher([
 const isApiRoute = createRouteMatcher(["/api/(.*)"]);
 
 export default clerkMiddleware(async (auth, req) => {
-  // Log for debugging
-  const authHeader = req.headers.get("authorization");
-  if (authHeader) {
-    log.debug("Authorization header present", {
-      preview: authHeader.substring(0, 20) + "...",
-    });
-  }
-
   // Don't protect public routes
   if (isPublicRoute(req)) {
     log.debug("Public route, skipping auth");