Photometry update

[dsavransky]

Describe your changes

Final cruft removal and docs update for 3.1.0 release. Also adding HWO Mission Stars target list.

Type of change

• New feature (non-breaking change which adds functionality)

Checklist before requesting a review

• [x] I have verified that all unit tests pass in a clean virtual environment and added new unit tests, as needed
• [x] I have run e2eTests and added new test scripts, as needed
• [x] I have verified that all docstrings are properly formatted and added new documentation, as needed