Enforce conventional commits and generate the changelog

[cdunster]

The goal is to generate a consistent changelog with as little user input as possible. For this to work with existing tooling the most common approach is to follow conventional commits and use a tool like git-cliff or cocogitto or others. Therefore, we also need to enforce conventional commits so we can use them to generate the changelog. My preference would be to enforce them in a PR instead of in pre-commit/pre-push hooks or branch protections so that we don't stop people pushing WIP commits just for testing.

AC

• Enforce conventional commits using existing tooling.
• Generate changelog on release.