Build Quartz from within the blumeops repo instead of copying files
to a separate location. This allows git to find file history for
the CreatedModifiedDate plugin, eliminating the "not tracked by git"
warnings.
Changes:
- Copy Quartz build system into workspace instead of vice versa
- Use symlinks for content and CHANGELOG.md
- Clean up build artifacts after creating tarball
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
