fix: resolve bugs in benchmark lifecycle, snapshot filtering, and dark mode

- Fix PVC bind loop leak on unmount via cancellation ref
- Fix DeleteOptions body structure for proper foreground propagation
- Filter snapshots to tns-csi driver only (was showing all drivers)
- Fix stale closures in Escape key handlers with useCallback
- Add loading state to cleanup delete button, remove window.confirm/alert
- Use CSS custom properties for protocol chart colors (dark mode support)
- Fix all 35 ESLint warnings (import sort, indent, boolean attrs)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/components/SnapshotsPage.tsx

@@ -12,9 +12,9 @@ import {
   StatusLabel,
 } from '@kinvolk/headlamp-plugin/lib/CommonComponents';
 import React from 'react';
-import { useTnsCsiContext } from '../api/TnsCsiDataContext';
 import type { VolumeSnapshot } from '../api/k8s';
 import { formatAge } from '../api/k8s';
+import { useTnsCsiContext } from '../api/TnsCsiDataContext';
 
 export default function SnapshotsPage() {
   const { volumeSnapshots, volumeSnapshotClasses, snapshotCrdAvailable, loading, error } =