[Hackathon] implement kontext client authorization

[d14c]

What?

Hackathon content ⚠️ Do not review, do not merge ⚠️

Why?

Checklist

• I have performed a self-review of my code.
• I have added tests for my changes.
• I have run linter locally (make lint) and all checks pass.
• I have run tests locally (make tests) and all tests pass.
• I have commented on my code, particularly in hard-to-understand areas.

Related PR(s)/Issue(s)

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