[EPIC] REST layer improvements (post-GA)

[bajtos]

• configurable response types/formats Configurable response types/formats #436
• serve OpenAPI spec from a controller method
• etag-based caching
• Allow controller methods to specify custom status code and contribute additional response headers
• streaming requests
• streaming responses File downloads (streaming responses) #2230
• handling file uploads File upload with multipart/form-data #1873
• etc.

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[stale]

This issue has been closed due to continued inactivity. Thank you for your understanding. If you believe this to be in error, please contact one of the code owners, listed in the CODEOWNERS file at the top-level of this repository.

[stale]

This issue has been marked stale because it has not seen activity within six months. If you believe this to be in error, please contact one of the code owners, listed in the CODEOWNERS file at the top-level of this repository. This issue will be closed within 30 days of being stale.

[stale]

This issue has been closed due to continued inactivity. Thank you for your understanding. If you believe this to be in error, please contact one of the code owners, listed in the CODEOWNERS file at the top-level of this repository.