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/javascript/settings.js

@@ -9,6 +9,7 @@
   'use strict';
   const P = window.Podman;
   let autostartNames = [];
+  let allContainerNames = [];
 
   function renderAutostart() {
     const tbody = P.el('autostart-tbody');
@@ -24,11 +25,24 @@
           '</div></td></tr>';
       }).join('')
       : '<tr><td colspan="3" class="podman-empty-note">No containers in the autostart chain.</td></tr>';
+    renderAddOptions();
+  }
+
+  // Repopulated after every add/remove so it only ever offers containers
+  // that exist and aren't already in the chain — avoids duplicate entries
+  // and offering a container name that no longer exists.
+  function renderAddOptions() {
+    const select = P.el('autostart-add-select');
+    const available = allContainerNames.filter(function (name) { return autostartNames.indexOf(name) === -1; });
+    select.innerHTML = available.length
+      ? available.map(function (name) { return '<option value="' + P.escapeHtml(name) + '">' + P.escapeHtml(name) + '</option>'; }).join('')
+      : '<option value="">All containers already added</option>';
+    P.el('autostart-add-btn').disabled = !available.length;
   }
 
   function saveAutostart() {
     return P.post('settings', 'autostart_save', { names: autostartNames }).catch(function (err) {
-      alert('Could not save autostart order: ' + err.message);
+      P.toast('Could not save autostart order: ' + err.message, 'error');
     });
   }
 
@@ -52,8 +66,19 @@
   }
 
   function load() {
-    return P.get('settings', 'get').then(fillForm).catch(function (err) {
-      alert('Could not load settings: ' + err.message);
+    return Promise.all([
+      P.get('settings', 'get').then(fillForm),
+      // Needed for the "Add container" dropdown — a separate, tolerant
+      // fetch so a containers.php hiccup doesn't also break the rest of
+      // Settings (autostart reorder/remove don't need this list at all).
+      P.get('containers', 'list').then(function (containers) {
+        allContainerNames = containers.map(function (c) { return c.name; }).sort();
+        renderAddOptions();
+      }).catch(function () {
+        allContainerNames = [];
+      }),
+    ]).catch(function (err) {
+      P.toast('Could not load settings: ' + err.message, 'error');
     });
   }
 
@@ -170,11 +195,11 @@
       P.post('disks', 'format', { device: select.value }).then(function (data) {
         close();
         P.el('settings-storage-path').value = data.mountPath;
-        alert('Formatted and mounted at ' + data.mountPath + '. Storage path has been filled in below — click "Save Settings" to use it, then Restart Podman.');
+        P.toast('Formatted and mounted at ' + data.mountPath + '. Click "Save Settings" below, then Restart Podman.', 'warn');
       }).catch(function (err) {
         submitBtn.disabled = false;
         submitBtn.textContent = 'Format Disk';
-        alert('Format failed: ' + err.message);
+        P.toast('Format failed: ' + err.message, 'error');
       });
     });
 
@@ -190,15 +215,24 @@
       stopTimeoutSeconds: parseInt(P.el('settings-stop-timeout').value, 10) || 10,
     };
     return P.post('settings', 'save', body).then(function () {
-      alert('Saved. Restart podman (rc.podman restart) to apply storage/enabled changes.');
+      P.toast('Saved. Restart podman (rc.podman restart) to apply storage/enabled changes.', 'warn');
     }).catch(function (err) {
-      alert('Save failed: ' + err.message);
+      P.toast('Save failed: ' + err.message, 'error');
     });
   }
 
   function init() {
     P.el('settings-save-btn').addEventListener('click', save);
 
+    P.el('autostart-add-btn').addEventListener('click', function () {
+      const select = P.el('autostart-add-select');
+      const name = select.value;
+      if (!name) return;
+      autostartNames.push(name);
+      renderAutostart();
+      saveAutostart();
+    });
+
     P.el('autostart-tbody').addEventListener('click', function (e) {
       const btn = e.target.closest('button[data-action]');
       if (!btn) return;