Support for API-Key based authentication

[dadrus]

Preflight checklist

• [X] I agree to follow this project's Code of Conduct.
• [X] I have read and am following this repository's Contribution Guidelines."
• [ ] I have discussed this feature request with the community.

Describe the background of your feature request

Many services make use of API-Keys for authentication purposes. Even heimdall has support for many different authentication mechanisms, it currently lacks support for API-Keys

Describe your idea

As the title sais, support for API-key based authentication would be helpful

Are there any workarounds or alternatives?

Not really. One could make use of JWT tokens for API keys, but that implies, the verification of these using keys from the corresponding jwks source. With API-keys, one would like to match the actual values.

Version

v0.13.0-alpha

Additional Context

No response