feat: add GraphControls component and useGraphData hook for knowledge graph management

src/components/admin/graph/GraphControls.jsx

@@ -0,0 +1,54 @@
+import { RefreshCw, AlertCircle } from 'lucide-react';
+import Button from '../../ui/Button';
+import SuggestionsQueue from '../SuggestionsQueue';
+
+/**
+ * Sidebar controls panel: the exclude-nodes toggle, the AI analysis button,
+ * and the R42 suggestions queue.
+ *
+ * Kept intentionally thin — all async logic lives in the KnowledgeGraph
+ * orchestrator and is injected via props.
+ */
+export default function GraphControls({
+  showExcludeNodes,
+  onShowExcludeChange,
+  onAnalyze,
+  isAnalyzing,
+  analyzeError,
+  disabled,
+  onApplied,
+}) {
+  return (
+    <div className="mb-6 pb-4 border-b border-bg-warm space-y-3">
+      <label className="flex items-center gap-2 text-sm text-fg-muted cursor-pointer">
+        <input
+          type="checkbox"
+          checked={showExcludeNodes}
+          onChange={e => onShowExcludeChange(e.target.checked)}
+          className="rounded bg-bg-warm border-transparent focus:ring-0 text-teal"
+        />
+        Show Excluded Nodes (Reference Material)
+      </label>
+
+      <div>
+        <Button
+          onClick={onAnalyze}
+          disabled={isAnalyzing || disabled}
+          className="w-full flex justify-center items-center gap-2"
+        >
+          <RefreshCw size={16} className={isAnalyzing ? 'animate-spin' : ''} />
+          {isAnalyzing ? 'Analyzing Graph…' : 'Analyze & Optimize Graph'}
+        </Button>
+
+        {analyzeError && (
+          <p className="mt-2 text-xs text-red-600 flex items-start gap-1">
+            <AlertCircle size={14} className="shrink-0 mt-0.5" />
+            {analyzeError}
+          </p>
+        )}
+      </div>
+
+      <SuggestionsQueue onApplied={onApplied} />
+    </div>
+  );
+}