Recursive type definition using Typebox in schema leads to broken swagger file

### Prerequisites

- [x] I have written a descriptive issue title
- [x] I have searched existing issues to ensure the bug has not already been reported

### Fastify version

5.1.0

### Plugin version

9.4.2

### Node.js version

22.12.0

### Operating system

macOS

### Operating system version (i.e. 20.04, 11.3, 10)

15.2

### Description

When using Recursive definition inside schema.body, swagger file generated as a result will be broken. It will generate `$ref: "#/components/schemas/def-0"`, but the "def-0" definition itself won't be generated.

The endpoint body is defined as follows:
```
import {Type, type Static} from '@sinclair/typebox';
const TreeNode = Type.Recursive(
(Node) =>
Type.Object({
name: Type.String(),
children: Type.Optional(Type.Array(Node)),
}),
{$id: 'Node'},
);

const BodySchema = Type.Object({
name: Type.String(),
age: Type.Number({minimum: 0}),
treeNodes: Type.Array(TreeNode),
});
type BodyType = Static;

// ...

server.register(
async (server: FastifyInstance) => {
return [
server.route({
method: 'POST',
url: 'submit',
handler: async (request, reply) => {
const body = request.body as BodyType;
reply.send({message: `Received: ${body.name}, ${body.age}`});
},
schema: {
operationId: 'testSubmit',
summary: 'Test',
description: 'Submit user data',
body: BodySchema,
response: {
200: Type.Object({
message: Type.String(),
}),
},
},
}),
]
},
{prefix: '/'},
);
```

The definition of the "/submit" endpoint in this example will generated as such:
```
/submit:
post:
operationId: testSubmit
summary: Test
description: Submit user data
requestBody:
content:
application/json:
schema:
type: object
properties:
name:
type: string
age:
minimum: 0
type: number
treeNodes:
type: array
items:
type: object
properties:
name:
type: string
children:
type: array
items:
$ref: "#/components/schemas/def-0"
required:
- name
title: Node
```
The problem is that the "def-0" schema definition will not be created in the resulting file.

### Link to code that reproduces the bug

https://gist.github.com/CruelCrow/2b5ee3ec6fbaecc474906cdaa45ba83e

### Expected Behavior

Recursive definition of an object should be created in the resulting swagger file.