feat: implement automatic, atomic, and push-based repository synchronization

- Switched from systemd path monitoring to a custom wrapper script `mxos-trigger-dist-repo.sh` spawned by the Koji signing spooler.
- Wrapper script runs Koji `dist-repo` synchronously and triggers the `mxos-repo-sync.sh` script to perform an atomic rsync of packages to the Caddy server.
- Excluded reposerver from distro-sync to work around VM disk space constraints.
- Configured Koji tag `mxos0` to cancel older pending/running `distRepo` tasks when a new one is triggered.
- Verified successful repository generation, synchronization, and DNF resolution.

Co-developed-by: Gemini AI <renich+gemini@woralelandia.com>
Signed-off-by: Rénich Bon Ćirić <renich@woralelandia.com>

roles/kojira/templates/kojira.conf.j2

@@ -2,3 +2,4 @@
 server = https://{{ koji_hub_fqdn }}/kojihub
 cert = {{ kojira_pem_path }}
 serverca = {{ koji_remote_ca_trust_path }}
+check_external_repos = true