feat: update to biome 2 for custom rules

[ntrpilot-lokalise]

Changes

• Updated the dev dependency to biome 2 (beta)
• Migrated the biome config files as some of the properties had changed since 1.x
• Created a custom biome rule to check that z-index can only have a design-token assigned
  • I had to make this a warning as I don't see a way to ignore error produced by plugins yet.
• Enforce the new warning for all frontend projects

Checklist

• Apply one of following labels; major, minor, patch or skip-release
• I've updated the documentation, or no changes were necessary
• I've updated the tests, or no changes were necessary

[kibertoad]

@ntrpilot-lokalise I think this requires a semver major label

[ntrpilot-lokalise]

@ntrpilot-lokalise I think this requires a semver major label

@kibertoad remind me how to do that? Do I change the prefix of the name of the PR from feat: to BREAKING CHANGE: .. or is it an actual label that I add to the PR?

[kibertoad]

@ntrpilot-lokalise no, in this repo we just use labels, attach "major".

btw, have you seen reply from biome folks about the rule ignores?