fix(studio): address code review nits - simplify extractBody, consistent Request creation

Agent-Logs-Url: https://github.com/objectstack-ai/framework/sessions/8923ba52-78fa-4a0c-8f11-edd6b20e611c

Co-authored-by: hotlong <50353452+hotlong@users.noreply.github.com>

Author: Copilot

apps/studio/server/index.ts

@@ -257,7 +257,6 @@ function extractBody(
     if (method === 'GET' || method === 'HEAD' || method === 'OPTIONS') return null;
 
     if (incoming.rawBody != null) {
-        if (typeof incoming.rawBody === 'string') return incoming.rawBody;
         return incoming.rawBody;
     }
 
@@ -346,9 +345,7 @@ export default getRequestListener(async (request, env) => {
 
     // For GET/HEAD/OPTIONS (or body-less requests): pass through with corrected URL.
     return await app.fetch(
-        url !== request.url
-            ? new Request(url, { method, headers: request.headers })
-            : request,
+        new Request(url, { method, headers: request.headers }),
     );
 });