overhaul app tracking and update orchestration

- Generate and ship a verified 389-app tracking catalog with 23 runtime overrides, fallback detectors, ports, logos, and Docker Hub tag previews.
- Support modern Proxmox VE Helper-Scripts markers, historical installations, and official or manual app deployments.
- Rework the LXC App and Updates tabs with cached suggestions, explicit discovery, version tracking, web links, custom updaters, and complete i18n.
- Add independent OS, app, Docker Engine, Docker image, bulk, and scheduled update targets.
- Add digest-based Docker inventory, Compose dependency grouping, safe standalone-container recreation with rollback, and package-scoped Docker Engine updates.
- Refresh per-LXC caches after lifecycle and update tasks, then emit idempotent notifications based on the verified final state.
- Harden Coral USB recovery by removing orphaned gasket DKMS registrations and validating that dpkg is healthy before reporting success.

AppImage/scripts/notification_templates.py

@@ -512,10 +512,7 @@ TEMPLATES = {
     },
     'lxc_update_applied': {
         'title': '{hostname}: LXC {ct_name} ({vmid}) update {result}',
-        'body': (
-            'Container {ct_name} (CT {vmid}) — update {result}.\n'
-            'Target: {target}    Duration: {duration}'
-        ),
+        'body': '{details}',
         'label': 'LXC update applied',
         'group': 'vm_ct',
         'default_enabled': True,
@@ -540,6 +537,16 @@ TEMPLATES = {
         # never received the notification they explicitly asked for.
         'default_enabled': True,
     },
+    'docker_stack_update_available': {
+        'title': '{hostname}: Docker updates available on CT {vmid}',
+        'body': (
+            'Container {ct_name} (CT {vmid}) has {count} Docker update(s):\n'
+            '{details}'
+        ),
+        'label': 'Docker updates available',
+        'group': 'updates',
+        'default_enabled': True,
+    },
     'vm_start': {
         'title': '{hostname}: VM {vmname} ({vmid}) started',
         'body': 'Virtual machine {vmname} (ID: {vmid}) is now running.',
@@ -1728,6 +1735,7 @@ EVENT_EMOJI = {
     'lxc_updates_available': '\U0001F4E6',     # \uD83D\uDCE6 package \u2014 pending CT updates
     'lxc_update_applied':   '\u2705',           # \u2705 check \u2014 update applied
     'app_update_available': '\U0001F195',  # \ud83c\udd95 NEW \u2014 upstream app release
+    'docker_stack_update_available': '\U0001F433',
     'vm_start':             '\u25B6\uFE0F',    # play button
     'vm_start_warning':     '\u26A0\uFE0F',     # warning sign - started with warnings
     'vm_stop':              '\u23F9\uFE0F',     # stop button