fix(defer): respect headers and status

Author: meetic-mikaelanzano

.changeset/nasty-carrots-breathe.md

@@ -0,0 +1,5 @@
+---
+"@remix-run/router": minor
+---
+
+Remix document response now respects headers and status code set in defer()

packages/router/__tests__/router-test.ts

@@ -12350,6 +12350,10 @@ describe("a router", () => {
                 "x-custom": "yes",
               }),
             },
+            statusCode: 201,
+            loaderHeaders: {
+              deferred: new Headers({ "x-custom": "yes" }),
+            }
           });
         });
 

packages/router/router.ts

@@ -3183,7 +3183,12 @@ async function callLoaderOrAction(
   }
 
   if (result instanceof DeferredData) {
-    return { type: ResultType.deferred, deferredData: result };
+    return {
+      type: ResultType.deferred,
+      deferredData: result,
+      statusCode: result.init?.status,
+      headers: result.init?.headers && new Headers(result.init.headers),
+    };
   }
 
   return { type: ResultType.data, data: result };