Support for the "Deprecation" Response Header (RFC 9745)

[roughconsensusandrunningcode]

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Is there an existing issue for this?

• [x] I have searched the existing issues

Is your feature request related to a problem? Please describe the problem.

Supporting the Deprecation Response Header and the Deprecation Link Relation Type for deprecated API version, as specified in RFC 9745

Describe the solution you'd like

A configurable Deprecation Policy, similar to Sunset Policy, like this

options.Policies.Deprecation(0.9)
  .Effective(2025, 3, 31)
  .Link("https://developer.example.com/deprecation")
    .Type("text/html");

that will produce as response headers

Deprecation: @1743379200
Link: <https://developer.example.com/deprecation>; rel="deprecation"; type="text/html"

Additional context

No response