v2.20.1

Fix installed self-update ownership checks for uv and pipx.

• Keep home-managed installations eligible for updates from home, nested, and unrelated directories.
• Preserve symlink launcher dispatch for ownership queries and upgrade commands while retaining project-launcher checks.

The fix includes 40 focused updater regression tests. Full local qualification passed 8,186 tests with 20 existing skips and 91.59% combined line and branch coverage.

See the changelog and updater fix.