Support Pushed Auth Request by RFC-9126

[migregal]

Follows https://github.com/zitadel/zitadel/issues/10239

Definition of Ready

• [x] I am happy with the code
• [x] Short description of the feature/issue is added in the pr description
• [x] PR is linked to the corresponding user story
• [x] Acceptance criteria are met
• [x] All open todos and follow ups are defined in a new ticket and justified
• [x] Deviations from the acceptance criteria and design are agreed with the PO and documented.
• [x] No debug or dead code
• [x] My code has no repetitions
• [ ] Critical parts are tested automatically
• [ ] Where possible E2E tests are implemented
• [x] Documentation/examples are up-to-date
• [x] All non-functional requirements are met
• [x] Functionality of the acceptance criteria is checked manually on the dev system.

[elinashoko]

Thanks for your contribution @migregal we'll have a look at your PR in our next sprint.

[muhlemmer]

Please take note of https://github.com/zitadel/oidc/discussions/785