fix(express): keep patched layer.handle writable

Co-Authored-By: gpt-5.3-codex-high <noreply@anthropic.com>

Author: cursoragent

packages/core/src/integrations/express/patch-layer.ts

@@ -46,6 +46,7 @@ export function patchLayer(options: ExpressPatchLayerOptions, layer?: ExpressLay
   Object.defineProperty(layer, 'handle', {
     enumerable: true,
     configurable: true,
+    writable: true,
     value: function layerHandlePatched(
       this: ExpressLayer,
       req: ExpressRequest,