Enforced by Biome with pre-commit hooks (simple-git-hooks + lint-staged).

• Formatter: 2-space indent, 100-char line width, double quotes, semicolons, trailing commas
• Linter: noUnusedImports/noUnusedVariables error; useImportType error; noExplicitAny/noNonNullAssertion warn
• TypeScript: Full strict (noUncheckedIndexedAccess, exactOptionalPropertyTypes, noImplicitOverride)
• Imports: import type for type-only imports (Biome enforced)