[BUG] `is not of type 'object'` when `#/` referencing

Bug Report Checklist

• Have you provided a full/minimal spec to reproduce the issue?
• Have you validated the input using an OpenAPI validator (example)?
• Have you tested with the latest master to confirm the issue still exists?
• Have you searched for related issues/PRs?
• What's the actual output vs expected output?

Description

I've been following the idea from https://github.com/OAI/OpenAPI-Specification/issues/1590#issuecomment-786447707 to "override" required field.

MySchema.yaml

type: object
properties:
  foo: 
    type: integer
  bar:
    type: integer
required:
  - foo
  - bar

src/spec.yaml

patch:      
  summary: Update something
  requestBody:
    content:                                     
      application/json:
        schema:
          type: object
          properties:
            $ref: ../components/schemas/MySchema.yaml#/properties

The generator fails on:

-attribute paths.'.....requestBody.content.'application/json'.schema.properties is not of type `object`

It feels like validation ignores #/properties. bundling with -dereference however recognizes the reference correctly and works fine but applying generator on a bundled & dereferenced spec is a so-so workaround because it loses the filename context and generated DTOs have very clunky naming.

I also tried to walk around this by having:
MySchemaProps.yaml

foo: 
    type: integer
  bar:
    type: integer

MySchema.yaml

type: object
properties:
  $ref: './MySchemaProps.yaml'

to avoid #/ ref, but I get

Caused by: com.fasterxml.jackson.databind.exc.MismatchedInputException: Cannot construct instance of `io.swagger.v3.oas.models.media.ObjectSchema` (although at least one Creator exists): no String-argument constructor/factory method to deserialize from String value ('./MySchemaProps.yaml')
 at [Source: UNKNOWN; byte offset: #UNKNOWN]

Again, bundling with -dereference works fine on this too but not generator.

Neither works an example from spec: https://github.com/OAI/OpenAPI-Specification/blob/main/versions/3.0.2.md#models-with-composition
all allOf props in Kotlin generator goes to some weird allOf-prefixed data class and there is no DTO with all of the properties in one place.

openapi-generator version

6.2.1

Related issues/PRs

• https://github.com/OAI/OpenAPI-Specification/issues/1590
• Maybe https://github.com/OpenAPITools/openapi-generator/issues/11151

Start by reproducing the failures with MySchema.yaml, src/spec.yaml, and MySchemaProps.yaml using the generator version described, then compare behavior with a bundled and dereferenced spec. Inspect the validation and reference-resolution path for schema properties and the Kotlin allOf example; done means valid local references and composition generate without the reported errors or clunky loss of context.