Rework Dashboard, add toasts, container folders/icons/WebUI links, detail tabs

Dashboard:
- Plain-count stat tiles (Running/Stopped/Pods/Images/Volumes/Networks)
  separated from a single "Resource Usage" card (CPU/Memory/Swap/Storage
  meter rows) instead of forcing both into one tile grid, which produced
  awkward spanning-tile/dead-cell layouts.
- Fixed CPU usage never changing (libpod's own cpuUtilization is computed
  once and never resampled) by computing it from /proc/stat deltas instead.
- Fixed memory usage reading far too high by using /proc/meminfo's
  MemAvailable instead of libpod's raw (non-reclaimable-aware) memFree.
- Added an Autostart Queue table reusing podman-autostart.sh's own
  failure-counter files.
- Dashboard and Containers now auto-refresh every ~2s (paused when the
  tab is hidden or a modal is open).

Toasts:
- Real success/warn/error/info toast notifications replacing every
  alert() used for one-way feedback, across every panel.

Container detail modal:
- 5 new tabs: Resources, Logs, Console, Events, Healthcheck.

Containers panel:
- Folders to group containers (name + icon), stored in the plugin's own
  folders.json — a folder's header always shows an icon+name+status chip
  per member, matching Unraid's own Docker page folders. "Move to
  Folder" becomes "Remove from Folder" once a container is already
  grouped.
- Containers can carry an icon URL and a WebUI URL (small button next to
  the name), both stored as container labels and auto-filled from
  templates where applicable.
- Settings: an "Add container" control for the Autostart order table.

Fixes:
- Context menus now measure their own rendered size and flip above the
  anchor when there isn't room below, instead of running off-screen.
- Containers table now uses table-layout:fixed with explicit column
  widths — auto layout was shifting every column (and the header) on
  every folder expand/collapse, and briefly again when a flex wrapper
  was mistakenly placed directly on a <td>.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

webui/plugins/podman/include/helpers.php

@@ -11,6 +11,37 @@
 
 declare(strict_types=1);
 
+/**
+ * Reads /usr/local/share/unraid-podman/installed-versions.env — the same
+ * manifest plugin/sbin/podman-verify-packages.sh and
+ * podman-update-packages.sh use (see plugin/podman.plg's postinstall step,
+ * which generates it) — shared here so settings.php (package version
+ * chips) and system.php (Dashboard's plugin version chip) both report
+ * exactly what those tools would, not two possibly-diverging readers of
+ * the same file.
+ *
+ * @return array<string,string>
+ */
+function podman_read_installed_versions(): array
+{
+    $path = '/usr/local/share/unraid-podman/installed-versions.env';
+    if (!is_readable($path)) {
+        return [];
+    }
+    $lines = file($path, FILE_IGNORE_NEW_LINES | FILE_SKIP_EMPTY_LINES) ?: [];
+    $out = [];
+    foreach ($lines as $line) {
+        $line = trim($line);
+        if ($line === '' || str_starts_with($line, '#')) {
+            continue;
+        }
+        if (preg_match('/^([A-Z_][A-Z0-9_]*)="?([^"]*)"?$/', $line, $m)) {
+            $out[$m[1]] = $m[2];
+        }
+    }
+    return $out;
+}
+
 function podman_format_bytes(int $bytes): string
 {
     if ($bytes <= 0) {