* Add justfile to simplify running all the tests
* Save all PBF outputs to the text files
* Consolidate all tests to reuse the same code
* Consolidate database initialization
* updated readme with the new instructions
Note that while this PR creates "expected" files, the CI cannot validate
the generated results because the output is not stable. Eventually we
may try to output just the non-geometry values to have reasonable tests
comparing against the expected results.
