Prepare documentation for alpha-release

[mkannwischer]

The following files should be updated prior to a alpha release:

• [ ] https://github.com/pq-code-package/mlkem-native/blob/main/.github/settings.yml
• [ ] https://github.com/pq-code-package/mlkem-native/blob/main/.github/pull_request_template.md
• [ ] https://github.com/pq-code-package/mlkem-native/blob/main/CODEOWNERS
• [ ] https://github.com/pq-code-package/mlkem-native/blob/main/CODE_OF_CONDUCT.md
• [ ] https://github.com/pq-code-package/mlkem-native/blob/main/CONTRIBUTING.md
• [ ] https://github.com/pq-code-package/mlkem-native/blob/main/GOVERNANCE.md
• [ ] https://github.com/pq-code-package/mlkem-native/blob/main/SECURITY.md
• [ ] https://github.com/pq-code-package/mlkem-native/blob/main/SUPPORT.md
• [ ] https://github.com/pq-code-package/mlkem-native/blob/main/.github/ISSUE_TEMPLATE/bug_report.md
• [ ] https://github.com/pq-code-package/mlkem-native/blob/main/.github/ISSUE_TEMPLATE/feature_request.md

Let's track the progress here. Some are straight-forward, some need some thinking (PR templates, issue templates), for some we can maybe ask for help from the PQCP TSC.

Please let me know if you think I missed something. @hanno-becker any other documentation you think we definitely need? We definitely need some text describing the release (see e.g., https://github.com/open-quantum-safe/liboqs/releases/tag/0.11.0).

@planetf1, could you maybe help us with making sure that we are not missing anything? I don't quite fully understand yet what should be part of CODE_OF_CONDUCT.md, CONTRIBUTING.md, GOVERNANCE.md, SECURITY.md, SUPPORT.md and which are strictly required. I'd stay close to liboqs for now.