support CORS in RPC

Author: lalexgap

packages/nitro-rpc-client/src/transport/http.ts

@@ -36,7 +36,13 @@ export class HttpTransport {
   ): Promise<unknown> {
     const url = new URL(`http://${this.server}`).toString();
 
-    const result = await axios.post(url.toString(), JSON.stringify(req));
+    const result = await axios.post(url.toString(), JSON.stringify(req), {
+      headers: {
+        "Access-Control-Allow-Origin": "*",
+        "Access-Control-Allow-Headers": "*",
+        "Access-Control-Expose-Headers": "*",
+      },
+    });
 
     return result.data;
   }