- config: env-based loading with startup validation, 13 tests - logger: structured slog wrapper with redaction, 10 tests - errors: unified AppError model with HTTP mapping, 18 tests - 41 tests total, build + vet clean
- config: env-based loading with startup validation, 13 tests - logger: structured slog wrapper with redaction, 10 tests - errors: unified AppError model with HTTP mapping, 18 tests - 41 tests total, build + vet clean