Always resolve Biome lint errors in changed files and verify provenance of pre-existing ones

The user's project enforces Biome linting (import sorting, import style such as explicit .ts extensions) through lint-staged pre-commit hooks. When biome check fails, identify whether errors are in files you modified or pre-existing in untouched source. Fix import sort/style violations within your own changes before committing. For errors in unmodified files, confirm they predate your work and report them as pre-existing rather than silently fixing or ignoring them.