refine post-install and hardware GPU docs, Monitor UX and CLI styling

- rewrite the 15 post-install pages and the 3 hardware GPU pages so they reflect the current scripts (reversibility, tracked-tool counts, kernel parameters, per-tool commands, Alpine LXC propagation flow)
- migrate the legacy step-badge helper on post-install/optional and create-vm/synology to the canonical pill component, with the stepLabel key added in each locale
- fix rich-text i18n calls missing helpers across network, automated, optional, security, customization and the post-install landing pages, and escape the `<iface>` placeholder in automated so intl no longer parses it as a tag
- remove the mouse-follow blue overlay from the docs landing layout
- reposition the App-tab Edit button and stack the Search and Register controls vertically on mobile
- move the Bulk update Configure/Edit control into the section header so it behaves the same on desktop and mobile
- show a spinner during the final autoremove/autoclean pass of update-pve-safe so the cleanup step reads as active instead of silent
- restyle the shell spinner and msg_info in a distinctive purple and drop the unused msg_lang duplicate
- add a web-docs i18n build script and its CI workflow, plus tests for the pushover notification channel

AppImage/scripts/notification_events.py

@@ -3817,21 +3817,13 @@ class PollingCollector:
             return 'secure_gateway_update_available', data
 
         if item_type == 'nvidia_xfree86':
-            kind = update.get('_upgrade_kind')
-            if kind == 'branch_upgrade':
-                upgrade_reason = (
-                    "Your current driver branch is no longer compatible with "
-                    f"kernel {update.get('_kernel') or 'this kernel'}. "
-                    "Switch to the recommended branch — the installer will "
-                    "rebuild against the running kernel."
-                )
-            else:
-                upgrade_reason = (
-                    "Same-branch maintenance update with bug/security fixes."
-                )
+            upgrade_reason = (
+                "Same-branch maintenance update with bug/security fixes. "
+                "The installer validates the selected release by rebuilding "
+                "its DKMS module against the running kernel."
+            )
             data = {
                 **common,
-                'kernel': update.get('_kernel') or '',
                 'upgrade_reason': upgrade_reason,
             }
             return 'nvidia_driver_update_available', data