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/managed_installs.py

@@ -1123,8 +1123,8 @@ def _check_oci_app(entry: dict) -> dict:
 #       returns the single newest version, e.g. "580.105.08"
 #   `https://download.nvidia.com/XFree86/Linux-x86_64/`
 #       HTML directory listing — we scrape it for per-branch latest
-#       (so a user on 570.x gets 570.x's latest, not pushed to 580.x
-#       unless their kernel forces a branch upgrade).
+#       (so a user on 570.x gets 570.x's latest, without an automatic
+#       cross-branch upgrade).
 #
 # Cache TTL is 7 days because NVIDIA's release cadence on each branch
 # is roughly monthly. The cache is in-memory only; AppImage restarts
@@ -1135,15 +1135,6 @@ _NVIDIA_CACHE_TTL = 7 * 86400
 _nvidia_cache: dict[str, Any] = {"versions": [], "fetched_at": 0}
 
 
-def _kernel_string() -> str:
-    try:
-        return subprocess.run(
-            ["uname", "-r"], capture_output=True, text=True, timeout=2,
-        ).stdout.strip()
-    except (OSError, subprocess.TimeoutExpired):
-        return ""
-
-
 def _version_tuple(v: str) -> tuple:
     """Convert ``580.105.08`` → ``(580, 105, 8)`` for comparison.
     Pads to 3 components so ``580.82`` < ``580.105.08``."""
@@ -1216,7 +1207,6 @@ def _check_nvidia_xfree86(entry: dict) -> dict:
         "last_check": _now_iso(),
         "error": None,
         "_upgrade_kind": "patch" if available else None,
-        "_kernel": _kernel_string(),
     }