I created multiple PRs to ease the diff. once merged, I'll rebase this one.

Main topic

• Community add-on support #184

Detail

• simplify community setup testing extract createSetupTest for reusable test setup #1000
• moving files to file in run phase rename to file, isKit, directory #999
• Introduced a transforms layer in sv-utils that wraps parse/callback/generate for each file format (script, css, svelte, json, yaml, etc.), so add-ons declare what to change rather than manually parsing and serializing. The engine detects these typed transforms via isTransform and auto-injects workspace context (language, etc.). This simplified all existing add-ons and made the pattern reusable for community add-ons. add transforms API and migrate all addons #1001
• split who exposes what refactor: move file helpers to sv-utils #1002
• closes: Allow community addons to have dependencies #77
• prevent my-cool-stuff-for-sv to be used (in step 1)
• version
  • check sv, it should be peerDep
  • sv-utils is a devDep
  • addon should have 0 Dep
• remove sv-add keyword of @sveltejs/sv-utils
• bump the few tests add-ons