Support for content in Response headers on UI, add mediatype to Header Parameters

[jeremyfiel]

Describe the problem to be solved
The current UI does not display the schema from a content keyword defined in Response headers.

---

If I use the same structure in Parameters, it seems to work as expected but it's missing the content type definition.

---

This small description should be derived from the mediatype mapping name

I think a reasonable location for this is just below the header/parameter name

Describe the solution you'd like

Display it similar to the Parameters section, with the media type and the schema definition.

Describe alternatives you've considered
none

Additional context

OpenAPI 3.1.1 example

openapi: 3.1.0
info:
  title: Example
  version: '0.0.1'
servers:
  - url: https://example.org
paths:
  '/foo/{example}':
    get:
      description: a sample URI
      parameters:
        - name: x-my-header
          in: header
          description: my custom header definition
          content:
            application/json:
              schema:
                type: array
                items:
                  type: object
                  additionalProperties: false
                  properties:
                    level:
                      enum:
                      - info
                      - warn
                      - error
                    message:
                      type: string
      responses:
        '200':
          description: OK
          headers:
            x-my-header:
              description: my custom header definition
              content:
                application/json:
                  schema:
                    type: array
                    items:
                      type: object
                      additionalProperties: false
                      properties:
                        level:
                          enum:
                          - info
                          - warn
                          - error
                        message:
                          type: string
          content:
            'application/json':
              schema: {}
        '400':
          description: Bad Request
          content: 
            'application/json':
              schema: {}