Add support for RFC9728 : OAuth 2.0 Protected Resource Metadata

[yannj-fr]

DO NOT SEND ANY SECURITY FIX HERE. Please read "Security Reporting" section on README.

What kind of change does this PR introduce? (check at least one)

• [ ] Bugfix
• [x] Feature
• [ ] Code style update
• [ ] Refactor
• [ ] Other, please describe:

Does this PR introduce a breaking change? (check one)

• [ ] Yes
• [x] No

If yes, please describe the impact and migration path for existing applications:

(If no, please delete the above question and this text message.)

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• [x] You consent that the copyright of your pull request source code belongs to Authlib's author.

[azmeuk]

Hi. Thank you for your contribution. I'll look more in depth in the spec and provide a review in the coming days/weeks. In the meantime, please consider adding unit tests and documentation.

[yannj-fr]

added the unit tests and documentation added support for internationalization of parameters

[yannj-fr]

let me cover additional implementation

[azmeuk]

Ok :pray: Please stick to signed_metadata, protected_resources and WWW-Authenticate. I would like to put more thoughts on the other topics before it gets implemented.

[sonarqubecloud[bot]]

Quality Gate failed

Failed conditions
2 Security Hotspots
3.8% Duplication on New Code (required ≤ 3%)

See analysis details on SonarQube Cloud