Zod schema references ($ref) breaking fastify route querystrings

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

4.26.1

Plugin version

No response

Node.js version

20.11.0

Operating system

Linux

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

20.04.4

Description

When using zod buildJsonSchemas to build the schema references, the querystring parameter in route schema breaks down.

// schema.ts

import { buildJsonSchemas } from 'fastify-zod'

...
const getPermissionsInputSchema = z.object({ users: z.array(z.string()) })

const { schemas: permissionSchemas, $ref } = buildJsonSchemas(
    {
        getPermissionsResponseSchema,
        getPermissionsInputSchema,
        getPermissionResponseSchema,
        updatePermissionsInputSchema,
        updatePermissionsResponseSchema,
        updatePermissionClaimsInputSchema,
        updatePermissionClaimsResponseSchema,
    },
    {
        $id: 'permissionSchemas',
    },
)

// route.ts

interface GetPermissionsInterface extends RouteGenericInterface {
    Querystring: GetPermissionsInput
}

server.get<GetPermissionsInterface>(
        '/permissions',
        {
            onRequest: [server.authenticate],
            schema: {
                tags: ['permissions'],
                description: 'For getting aggregate permissions of a collection of users',
                querystring: $ref('getPermissionsInputSchema'),
                response: { '2xx': $ref('getPermissionsResponseSchema') },
            },
        },
        getPermissionsHandler,
)

Swagger looks like it is trying to include every schema in the permission schemas collection, instead of the required getpermissionsInputSchema:

Link to code that reproduces the bug

No response

Expected Behavior

I would expect this to show the query parameters as it shows them for the "body" or "response" segment. I am quite confused why it's not doing so.

I found other bugs that seemed somewhat related to this, but none of them seemed to have resolved properly.

fastify / fastify-swagger