Fix: Service management errors in sigvild-gallery restoration

- Fix Unix timestamp conversion in restore.yml using proper strftime syntax
- Add service existence check before stopping sigvild-gallery service
- Fix systemd service template environment variable syntax error
- Add proper error handling for fresh deployments where service doesn't exist yet

Resolves service management failures during restoration on fresh VPS installations.

roles/sigvild-gallery/tasks/restore.yml

@@ -17,7 +17,7 @@
 
 - name: Display found backup files
   debug:
-    msg: "Found backup: {{ item.path }} ({{ (item.size / 1024 / 1024) | round(2) }}MB, {{ item.mtime | to_datetime }})"
+    msg: "Found backup: {{ item.path }} ({{ (item.size / 1024 / 1024) | round(2) }}MB, {{ '%Y-%m-%d %H:%M:%S' | strftime(item.mtime | int) }})"
   loop: "{{ backup_files.files | sort(attribute='mtime') }}"
   when: backup_files.files | length > 0
 
@@ -33,6 +33,15 @@
     - existing_data.stat.exists
     - backup_files.files | length > 0
 
+- name: Skip restore due to existing data
+  debug:
+    msg:
+      - "🛡️ SAFETY: Restore skipped to protect existing data"
+      - "Remove {{ sigvild_gallery_data_dir }}/data.db manually to enable restore"
+  when: 
+    - existing_data.stat.exists
+    - backup_files.files | length > 0
+
 - name: Restore from latest backup
   block:
     - name: Get latest backup file
@@ -45,12 +54,22 @@
           - "Restoring from latest backup: {{ latest_backup | basename }}"
           - "Target directory: {{ sigvild_gallery_data_dir }}"
 
+    - name: Check if sigvild-gallery service exists
+      stat:
+        path: /etc/systemd/system/sigvild-gallery.service
+      register: sigvild_service_file
+
     - name: Stop sigvild-gallery service before restoration
       systemd:
         name: sigvild-gallery
         state: stopped
       register: service_stopped_for_restore
-      ignore_errors: true  # Service might not exist on fresh deployment
+      when: sigvild_service_file.stat.exists
+      ignore_errors: true
+
+    - name: Display service stop status
+      debug:
+        msg: "{{ 'Service stopped for restoration' if sigvild_service_file.stat.exists else 'Service does not exist yet - skipping stop' }}"
 
     - name: Upload backup to remote server
       copy:
@@ -116,11 +135,13 @@
           - "Restored data size: {{ restored_size.stdout }}"
           - "Location: {{ sigvild_gallery_data_dir }}"
 
-  when: backup_files.files | length > 0
+  when: 
+    - backup_files.files | length > 0
+    - not existing_data.stat.exists
 
 - name: No backup available message
   debug:
     msg:
       - "ℹ️ No backup files found - starting with fresh installation"
       - "Data directory will be created empty: {{ sigvild_gallery_data_dir }}"
-  when: backup_files.files | length == 0
+  when: backup_files.files | length == 0