[FEATURE] (type-safe-api) Better code generation for "default" responses in OpenAPI

[cogwirrel]

Describe the feature

OpenAPI lets you define a default response.

Currently code generation treats this as a 0 response code, however we should generate code which conforms better to the specification.

Use Case

More intuitive behaviour for a given OpenAPI spec.

Proposed Solution

• Handler wrappers should allow returning any response code (ideally other than other defined responses) with alongside the modelled response.
• Clients/hooks should deserialise responses to the appropriate modelled response for any default responses with 2XX codes. Possibly combine with [FEATURE] Return error message sent from backend instead of standard message in ResponseError #821 to deserialise error responses too.

Other Information

No response

Acknowledgements

• I may be able to implement this feature request
• This feature might incur a breaking change

PDK version used

0.23.60

What languages will this feature affect?

Typescript, Java, Python

Environment details (OS name and version, etc.)

OSX