Restructure repo layout, wiring src/ and packaging for local and distro builds

- 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

scripts/installation/centos/package.sh

@@ -4,8 +4,17 @@ set -euo pipefail
 echo "[centos/package] Setting up rpmbuild directories..."
 mkdir -p /root/rpmbuild/{BUILD,RPMS,SOURCES,SPECS,SRPMS}
 
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+PROJECT_ROOT="$(cd "${SCRIPT_DIR}/../.." && pwd)"
+SPEC_PATH="${PROJECT_ROOT}/packaging/fedora/package-manager.spec"
+
+if [[ ! -f "${SPEC_PATH}" ]]; then
+  echo "[centos/package] ERROR: SPEC file not found: ${SPEC_PATH}"
+  exit 1
+fi
+
 echo "[centos/package] Extracting version from package-manager.spec..."
-version="$(grep -E '^Version:' package-manager.spec | awk '{print $2}')"
+version="$(grep -E '^Version:' "${SPEC_PATH}" | awk '{print $2}')"
 if [[ -z "${version}" ]]; then
   echo "ERROR: Version missing!"
   exit 1
@@ -15,13 +24,13 @@ srcdir="package-manager-${version}"
 echo "[centos/package] Preparing source tree: ${srcdir}"
 rm -rf "/tmp/${srcdir}"
 mkdir -p "/tmp/${srcdir}"
-cp -a . "/tmp/${srcdir}/"
+cp -a "${PROJECT_ROOT}/." "/tmp/${srcdir}/"
 
 echo "[centos/package] Creating source tarball..."
 tar czf "/root/rpmbuild/SOURCES/${srcdir}.tar.gz" -C /tmp "${srcdir}"
 
 echo "[centos/package] Copying SPEC..."
-cp package-manager.spec /root/rpmbuild/SPECS/
+cp "${SPEC_PATH}" /root/rpmbuild/SPECS/
 
 echo "[centos/package] Running rpmbuild..."
 cd /root/rpmbuild/SPECS