Fix public SDK license metadata

[kronk-bot]

Summary

• align both message packages with the public mirror's BSD-3-Clause root license
• correct the Python distribution metadata to match its existing BSD-3-Clause package metadata and license
• remove all remaining proprietary-license claims from the repository
• update the Black hook from 22.3.0 to 26.5.1 so the repository's all-files pre-commit CI works on Python 3.14

Validation

• all non-Docker pre-commit hooks passed across the repository (local Hadolint was blocked by the host Docker shim)
• parsed every package.xml and confirmed each declares BSD-3-Clause
• verified no Proprietary metadata remains
• git diff --cached --check

Closes PickNikRobotics/moveit_pro#21548

Release notes

None

[rlpratt12]

Note from Josh: Approved. However, we need to verify parity in moveit_pro for those packages. I thought they were just Copybara'd out, but looking at the commit history on the main branch of that repo, that doesn't seem to hold.