Bundler breaks external schemas with self-references

[califlower]

Problem

When bundling OpenAPI specs, external schemas that contain self-references get inlined, but their internal $ref pointers remain unchanged, creating dangling references that cause composition to fail.

Example

main.yaml:

openapi: 3.1.0
paths:
  /tree:
    get:
      responses:
        '200':
          content:
            application/json:
              schema:
                $ref: './external.yaml#/components/schemas/Tree'

external.yaml:

components:
  schemas:
    Tree:
      type: object
      properties:
        name:
          type: string
        children:
          type: array
          items:
            $ref: '#/components/schemas/Tree'  # Self-reference

Expected Behavior

The Tree schema should be copied to the root document's components with the self-reference remaining valid (or it should do what was done before, and should be left alone):

components:
  schemas:
    Tree:
      type: object
      properties:
        name:
          type: string
        children:
          type: array
          items:
            $ref: '#/components/schemas/Tree'  # Still valid

Actual Behavior

The Tree schema body is inlined directly into the response, but the self-reference still points to #/components/schemas/Tree, which doesn't exist in the root document:

paths:
  /tree:
    get:
      responses:
        '200':
          content:
            application/json:
              schema:
                type: object
                properties:
                  name:
                    type: string
                  children:
                    type: array
                    items:
                      $ref: '#/components/schemas/Tree' 

Calling BundleBytesComposed() fails with:

component `#/components/schemas/Tree` does not exist in the specification

[califlower]

I think it's because

if mappedReference != nil && mappedReference.Circular {
      if idx.GetLogger() != nil {
          idx.GetLogger().Warn("[bundler] skipping circular reference",
              "ref", sequenced.FullDefinition)
      }
  }
``` no longer exists