* feat: enhance connector functionality with multiple labels and line types
- Add support for three line types: single, double, and double with circle
- Implement start, center, and end labels with independent height controls
- Add custom RGB color picker for connectors and rectangles
- Increase spacing between double lines for better visibility
- Offset start/end labels by one tile to prevent node overlap
- Fix label filtering to show connectors with any label type
- Improve slider UI spacing to prevent interaction issues
Closes#107Closes#113
* Updated test suite and CI/CD workflow to include testing
* fix: sync package-lock.json with package.json for CI
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Co-authored-by: Stan <stanleylsmith@pm.me>
Implements automated Docker image building and pushing to Docker Hub
on commits to main/master branches. Supports multi-platform builds
(linux/amd64 and linux/arm64) with GitHub Actions caching for
improved performance.
