[bojemoi_boot] refactor(boot): ajouter telegram_net + 14 configs depuis stack base

Commit `ddbceb9`

networks: ajoute telegram_net (overlay, name: telegram_telegram_net)
configs: migre 14 entrées depuis 01-service-hl.yml (alertmanager, prometheus, loki, tempo, alloy, grafana-ini, grafana-datasources, grafana-dashboards-provider, postfix, provisioning_env, postgres_init_sql, rsync_rsyncd, rsync_jobs, tls_alertmanager_config) — boot est désormais la source unique des configs

Co-Authored-By: Claude Sonnet 4.6 noreply@anthropic.com