feat: initial Polaris Headlamp plugin (v0.0.1)

Sidebar page at /polaris that reads Fairwinds Polaris audit results
from ConfigMap/polaris-dashboard in the polaris namespace. Displays
cluster score, check summary (pass/warning/danger counts), and
cluster info. Caches results with user-configurable refresh interval.
Handles 403, 404, and malformed JSON error states.

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

src/index.tsx

@@ -0,0 +1,22 @@
+import {
+  registerRoute,
+  registerSidebarEntry,
+} from '@kinvolk/headlamp-plugin/lib';
+import React from 'react';
+import PolarisView from './components/PolarisView';
+
+registerSidebarEntry({
+  parent: null,
+  name: 'polaris',
+  label: 'Polaris',
+  url: '/polaris',
+  icon: 'mdi:shield-check',
+});
+
+registerRoute({
+  path: '/polaris',
+  sidebar: 'polaris',
+  name: 'polaris',
+  exact: true,
+  component: () => <PolarisView />,
+});