Biome: Use biome.json version as main

[nginx-jack]

Biome: Use biome.json version as main

This PR does not update the biome version

Adds install-help target, which given a local version of 2.2.2, and a biome.json version of 2.2.3, will output the following:

❯ make install-help

🛠️  Install options for biome v2.2.3:

1) 🧪 Install manually via Homebrew (advanced):
   # Find the correct commit SHA for biome 2.2.3 here:
   # https://github.com/Homebrew/homebrew-core/commits/master/Formula/biome.rb
   curl -sSL https://raw.githubusercontent.com/Homebrew/homebrew-core/<COMMIT_SHA>/Formula/biome.rb -o biome.rb
   brew install ./biome.rb
   brew pin biome

2) 🚀 Install via npm (global):
   npm install -g @biomejs/[email protected]

3) 🧰 Use temporarily via npx (auto fallback in Makefile):
   npx -y @biomejs/[email protected] <command>

Note: This Makefile will automatically fall back to npx if the right version is not found locally.

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[lamATnginx]

Add biome.rb to .gitignore

[TasoOneAsia]

Non blocking, but we should document these initial setup commands somewhere (maybe in a "Local development" section in the README? open to suggestions).