fix: migrate legacy app backup data (apphub_data restic-repo) during upgrade

When upgrading from legacy Cockpit architecture, the apphub_data volume
(containing the Restic backup repository at backup/restic-repo/) was not
included in LEGACY_VOLUME_ROLES. This caused all historical app volume
backup snapshots to be lost after migration.

- Add apphub_data to LEGACY_VOLUME_NAMES/ROLES and legacy_role_candidates
- Mount apphub_data volume readonly during legacy transform
- Copy backup/restic-repo from legacy volume into new data root

Author: zhaojing1987

install/lib/common.sh

@@ -44,8 +44,8 @@ DEFAULT_ARTIFACT_BASE="https://artifact.websoft9.com/websoft9"
 # ---------------------------------------------------------------------------
 LEGACY_CONTAINER_NAMES=(websoft9-apphub websoft9-deployment websoft9-git websoft9-proxy)
 LEGACY_CONTAINER_CANDIDATES=(websoft9-apphub websoft9-deployment websoft9-git websoft9-proxy websoft9-appmanage websoft9-portainer websoft9-gitea websoft9-nginxproxymanager websoft9-redis)
-LEGACY_VOLUME_NAMES=(apphub_logs apphub_media apphub_config portainer gitea nginx_data nginx_letsencrypt nginx_modsec nginx_var)
-LEGACY_VOLUME_ROLES=(apphub_logs apphub_media apphub_config portainer gitea nginx_data nginx_letsencrypt nginx_modsec nginx_var)
+LEGACY_VOLUME_NAMES=(apphub_logs apphub_media apphub_config apphub_data portainer gitea nginx_data nginx_letsencrypt nginx_modsec nginx_var)
+LEGACY_VOLUME_ROLES=(apphub_logs apphub_media apphub_config apphub_data portainer gitea nginx_data nginx_letsencrypt nginx_modsec nginx_var)
 LEGACY_SYSTEMD_UNITS=(websoft9.service cockpit.socket cockpit.service)
 LEGACY_HOST_COMPOSE_DIR="/data/compose"
 LEGACY_INSTALL_DIR="/data/websoft9/source"
@@ -130,6 +130,7 @@ legacy_role_candidates() {
     apphub_logs) printf '%s\n' apphub_logs ;;
     apphub_media) printf '%s\n' apphub_media ;;
     apphub_config) printf '%s\n' apphub_config ;;
+    apphub_data) printf '%s\n' apphub_data ;;
     portainer) printf '%s\n' portainer portainer_data ;;
     gitea) printf '%s\n' gitea gitea_data ;;
     nginx_data) printf '%s\n' nginx_data ;;

install/lib/upgrade-legacy.sh

@@ -341,6 +341,13 @@ if [ -d /legacy/apphub_logs ]; then
   cp -a /legacy/apphub_logs/. /data/logs/legacy-apphub/ 2>/dev/null || true
 fi
 
+# ---------------- Legacy AppHub backup (restic-repo) ----------------
+if [ -d /legacy/apphub_data/backup/restic-repo ]; then
+  log_step "Copying legacy app backup repository (restic-repo)"
+  mkdir -p /data/backup/restic-repo
+  cp -a /legacy/apphub_data/backup/restic-repo/. /data/backup/restic-repo/ 2>/dev/null || true
+fi
+
 # ---------------- Legacy config handoff ----------------
 cfg=""
 sysini=""
@@ -442,6 +449,7 @@ _legacy_transform_volumes() {
   _add_ro_volume apphub_config     apphub_config
   _add_ro_volume apphub_logs       apphub_logs
   _add_ro_volume apphub_media      apphub_media
+  _add_ro_volume apphub_data       apphub_data
   local host_compose_dir service_root_dir download_root_dir
   host_compose_dir="$(legacy_host_compose_dir 2>/dev/null || true)"
   service_root_dir="$(legacy_service_root_dir 2>/dev/null || true)"