Setup CI for linting

[jpmckinney]

• chore: Run safe Biome fixes (biome check --indent-style=space --line-width=119 . --apply)
• chore: Add biome.json (with formatter.indentWidth 2 to match current style)
• chore: Remove Husky and lint-staged (use pre-commit), commitlint and VS Code settings
• chore: Remove mentions of .env.example
• chore: Build produces identical output without tsconfig.node.json
• chore: Align .dockerignore with cookiecutter (build reads .env.production)
• chore: Simplify .gitignore
• chore: Remove Prettier
• chore: Fix lint/style/noUnusedTemplateLiteral
• chore: Fix lint/a11y/useGenericFontNames
• chore: Remove eslint-disable comments
• chore: Replace eslint with biome
• chore: Remove package scripts
• chore: Fix lint/complexity/useOptionalChain
• chore: Fix lint/suspicious/noConfusingVoidType
• chore: Fix lint/suspicious/noImplicitAnyLet
• chore: Ignore rules that fail 1-2 times. Format index.css.
• ci: Add lint workflow, and make docker workflow depend on it, closes #78

[jpmckinney]

@yolile You can look at individual commits - the full diff is large mostly due to the first commit.