- Add .golangci.yml with minimal linters (govet, ineffassign)
- Run gofmt -s and goimports on all files to fix formatting
- Disable fieldalignment and copylocks checks in govet
- 12 test functions covering all estimator functionality
- Tests for progress tracking, time calculations, formatting
- Tests for edge cases (zero items, no progress, etc.)
- All tests passing (12/12)