[routing-utils] Update routes schema for new property (#6860)

Adds an additional property for the `routes` schema. 

### Related Issues

N/A

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#### Tests

- [x] The code changed/added as part of this PR has been covered with tests
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packages/routing-utils/src/schemas.ts

@@ -150,6 +150,22 @@ export const routesSchema = {
               },
             },
           },
+          middleware: {
+            type: 'object',
+            required: ['id', 'type'],
+            additionalProperties: false,
+            properties: {
+              id: {
+                type: 'string',
+                maxLength: 256,
+              },
+              type: {
+                type: 'string',
+                maxLength: 32,
+                enum: ['v8-worker'],
+              },
+            },
+          },
           has: hasSchema,
         },
       },

packages/routing-utils/src/types.ts

@@ -36,6 +36,10 @@ export type Source = {
     redirect?: Record<string, string>;
     cookie?: string;
   };
+  middleware?: {
+    id: string;
+    type: 'v8-worker';
+  };
 };
 
 export type Handler = {