PM owns Python dependency generations. Shared frontend builders own Node
preparation and compilation. Route source updates and launchers through
these owners instead of separate repair ladders.
Remove obsolete live-venv holder gates and soft build-failure plumbing.
Preserve source validation, staged publication, fleet outcomes, and
historical relaunch hooks.
Verification: 956 tests passed in the combined focused run, with 43 skips.
After the final ZIP exit fix, 583 focused tests passed. Shared JavaScript
builder tests, Ruff, and diff checks passed. Native Windows/macOS and full
packaged-app builds were not run.