Scripts that were previously run via:
poetry run python ./SCRIPT_NAME.py
and have been moved, can now be run as:
poetry run SCRIPT_NAME
Some top-level scripts remain, where they only generate test vectors and
do not contain any Zcash logic. These now use the `zcash_test_vectors`
package, and can't be run directly unless this package is made available
in `PYTHONPATH`.