feat: support copy action

[danielkov]

Copy action for Overlay Specification v1.1.0

• Moved from feat: implement copy action openapi-overlay#21

Adds support for the copy action from Overlay Specification v1.1.0, enabling node duplication and move operations within OpenAPI documents.

Changes

• New functionality: copy field in Action schema allows copying nodes via JSONPath source selector
• Precedence: actions processed as remove > update > copy (copy ignored when remove=true or update exists)
• Move pattern: combine copy + remove actions to move nodes
• Validation: strict mode enforces single-match source selector and existing source/target paths
• Deep copy: cloned nodes prevent reference issues; merges into existing targets

Example

overlay: 1.1.0
x-speakeasy-jsonpath: rfc9535
info:
  title: Version Header Overlay
  version: 1.0.0
actions:
  # First, add X-API-Version header to each operation response
  - target: $.paths.*.*.responses.*
    description: Add X-API-Version header to all responses
    update:
      headers:
        XAPIVersion:
          schema:
            type: string
            const: ""
  # Then, copy the spec version into each X-API-Version header value
  - target: $.paths.*.*.responses.*.headers.XAPIVersion.schema.const
    description: Copy spec version to X-API-Version header const value
    copy: $.info.version

Overlay

openapi: 3.1.0
info:
  title: Version Header Test API
  version: 2.5.0
  description: API for testing version header copy
paths:
  /users:
    get:
      operationId: getUsers
      summary: Get users
      responses:
        '200':
          description: Successful response
    post:
      operationId: createUser
      summary: Create user
      responses:
        '201':
          description: Created
  /orders:
    get:
      operationId: getOrders
      summary: Get orders
      responses:
        '200':
          description: Successful response

Spec

openapi: 3.1.0
info:
  title: Version Header Test API
  version: 2.5.0
  description: API for testing version header copy
paths:
  /users:
    get:
      operationId: getUsers
      summary: Get users
      responses:
        '200':
          description: Successful response
          headers:
            XAPIVersion:
              schema:
                type: string
                const: "2.5.0"
    post:
      operationId: createUser
      summary: Create user
      responses:
        '201':
          description: Created
          headers:
            XAPIVersion:
              schema:
                type: string
                const: "2.5.0"
  /orders:
    get:
      operationId: getOrders
      summary: Get orders
      responses:
        '200':
          description: Successful response
          headers:
            XAPIVersion:
              schema:
                type: string
                const: "2.5.0"

Result

[TristanSpeakEasy]

LGTM once the CI pipeline passes