API Console feature

Implement API Console functionality.

Each method in ReDoc will have a button: “Try this method” which will open interactive console modal window.

There is the list of key features that should be implemented in the first version:

• Ability to send GET, POST, PUT, DELETE, UPDATE requests
• Ability to input/use/save authorization credentials
• Show UI for easy entering parameters for path, headers, query and body (payload) parameters
• UI should show selectbox for enums, checkboxes for boolean, text input for other simple types
• Request should be validated before send according to OpenAPI spec
• Support different environments (e.g. sandbox, dev, testing, etc) through OpenAPI vendor extension (each env will have unique base url and description) + ability to set default env specially for API-console
• For most parts response will be shown “as is”. JSON response will be only prettified (with possibility of collapsing). The other responses will be represented as strings.
• Show response headers that are documented in swagger. HTTP response headers that are not documented will be hidden under “Show undocumented response headers” button

The issue names no files, tests, or entry points, so first map the existing ReDoc API documentation UI and its OpenAPI request models. Define the console scope and design before implementation; done requires the listed request, authorization, parameter, validation, environment, and response-display behaviors.