* Move Arch-specific ignore rules into `packaging/arch/.gitignore` and simplify top-level `.gitignore`/`.dockerignore`.
* Update Arch `PKGBUILD` to sync from the project root and drop `packaging/` from the installed tree.
* Fix OS-specific `package.sh` helpers to resolve the new `packaging/*` locations correctly for Arch, Debian/Ubuntu, Fedora, and CentOS.
- Add dev runner main.py that prefers local src/ over installed pkgmgr
- Move Arch/Debian/Fedora packaging files under packaging/* and update build scripts
- Adjust .gitignore/.dockerignore for new packaging paths and src/source/
- Improve config defaults discovery to support src/ layout and installed packages
- Update architecture diagram and add TODO overview for TAGS/MIRROR/SIGNING_KEY
https://chatgpt.com/share/693a76a0-e408-800f-9939-868524cbef4d
- Add .dockerignore rules to prevent Arch package artifacts from entering the build context
- Rework Dockerfile to remove stale package artifacts before makepkg and use a dev entry script
- Introduce docker-entry-dev.sh to always rebuild pkgmgr from the mounted /src tree
- Update Makefile 'test' target to rebuild pkgmgr inside the container before running tests
- Fix predictable makepkg failures caused by residual *.pkg.tar.* files
Conversation reference: https://chatgpt.com/share/6935e6e8-f3fc-800f-a4e9-7537114f13d1
