Refactor: Simplify configuration and remove redundant variables

- Remove redundant variables: BACKUP_USER, BACKUP_STORAGE_PATH, BACKUP_REPO_NAME
- Add common Docker variables: PUID, PGID, TZ for centralized management
- Fix PROJECT_ROOT and SERVICES_BASE_DIR path calculations
- Reorganize configuration sections for better clarity
- Export common variables for use across services

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

backup.env.sample

@@ -6,9 +6,16 @@
 # Utilisateur système qui exécutera les backups
 CITADEL_USER="${CITADEL_USER:-citadel}"
 # Racine du projet citadel
-PROJECT_ROOT="${PROJECT_ROOT:-/home/nicolas/dev/citadel}"
+PROJECT_ROOT="${PROJECT_ROOT:-/home/citadel}"
 # Répertoire contenant les services à sauvegarder
-SERVICES_BASE_DIR="${SERVICES_BASE_DIR:-/home/$CITADEL_USER/services}"
+SERVICES_BASE_DIR="${SERVICES_BASE_DIR:-$PROJECT_ROOT/services}"
+
+# === Variables Communes ===
+# User/Group IDs pour les containers Docker
+PUID="${PUID:-1000}"
+PGID="${PGID:-1000}"
+# Timezone globale
+TZ="${TZ:-Europe/Paris}"
 
 # === Stockage Restic ===
 # Chemin de base pour le stockage des backups
@@ -25,7 +32,7 @@ LOG_DIR="${LOG_DIR:-/var/log}"
 # Répertoire temporaire
 TEMP_DIR="${TEMP_DIR:-/tmp}"
 # Fichier de configuration Restic (généré automatiquement)
-RESTIC_CONFIG_FILE="${RESTIC_CONFIG_FILE:-$PROJECT_ROOT/config/restic.conf}"
+RESTIC_CONFIG_FILE="${RESTIC_CONFIG_FILE:-$HOME/.config/citadel/restic.conf}"
 
 # === Politique de Rétention ===
 # Nombre de sauvegardes quotidiennes à conserver
@@ -38,14 +45,11 @@ RETENTION_MONTHLY="${RETENTION_MONTHLY:-12}"
 RETENTION_YEARLY="${RETENTION_YEARLY:-3}"
 
 # === Variables Dérivées (automatiquement calculées) ===
-BACKUP_USER="$CITADEL_USER"
 BACKUP_HOME="${BACKUP_HOME:-/home/$CITADEL_USER}"
 BACKUP_BASE_DIR="${BACKUP_BASE_DIR:-$BACKUP_HOME/backup}"
-BACKUP_STORAGE_PATH="$RESTIC_STORAGE"
-BACKUP_REPO_NAME="$RESTIC_REPO"
 BACKUP_REPOSITORY="${BACKUP_REPOSITORY:-$RESTIC_STORAGE/$RESTIC_REPO}"
 RESTIC_CACHE_DIR="${RESTIC_CACHE_DIR:-$TEMP_DIR/restic-cache}"
-CONFIG_DIR="${CONFIG_DIR:-$PROJECT_ROOT/config}"
+CONFIG_DIR="${CONFIG_DIR:-$HOME/.config/citadel}"
 SYSTEMD_DIR="${SYSTEMD_DIR:-/etc/systemd/system}"
 SERVICE_TEMPLATE="${SERVICE_TEMPLATE:-service-backup@.service}"
 TIMER_TEMPLATE="${TIMER_TEMPLATE:-service-backup@.timer}"
@@ -53,3 +57,8 @@ TIMER_TEMPLATE="${TIMER_TEMPLATE:-service-backup@.timer}"
 # === Variables d'export pour Restic ===
 export RESTIC_REPOSITORY="$BACKUP_REPOSITORY"
 export RESTIC_CACHE_DIR
+
+# === Variables d'export communes ===
+export PUID
+export PGID
+export TZ