PACKABUNCHAS upstream source

Repository: https://github.com/MattiaFortunati/packabunchas
Commit: fc4e6331fa4b8c17cc341094e9027bccd02f463f
The original MIT license is available at /licenses/packabunchas/LICENSE.txt.
ZzFX, ZzFXM and Stack Exchange attribution notices are available at /licenses/packabunchas/THIRD-PARTY-NOTICES.txt.
The local lerp expression replaces the CodePen-linked helper; source and adapted SHA-256 hashes are recorded in provenance.json.
The Denny Games lifecycle bridge is maintained in vendor/packabunchas/ and src/games/packabunchas/.