fix(canvas): Bug fixes for node movement, drag-drop, config panel, and introspection

- SpecRenderer: Add localNodes state with applyNodeChanges for smooth node dragging
- SpecRenderer: Fix getDefaultNodeData() - extractor uses 'custom_function' type with function definition
- SpecRenderer: Fix constraint default - use constraint_type instead of type
- CanvasView: Show config panel INSTEAD of chat when node selected (not blocked)
- NodeConfigPanelV2: Enable showHeader for code editor toolbar (Generate/Snippets/Validate/Test buttons)
- NodeConfigPanelV2: Pass studyId to IntrospectionPanel
- IntrospectionPanel: Accept studyId prop and use correct API endpoint
- optimization.py: Search multiple directories for model files including 1_setup/model/

atomizer-dashboard/frontend/src/components/canvas/panels/IntrospectionPanel.tsx

@@ -20,6 +20,7 @@ import { useCanvasStore } from '../../../hooks/useCanvasStore';
 
 interface IntrospectionPanelProps {
   filePath: string;
+  studyId?: string;
   onClose: () => void;
 }
 
@@ -56,7 +57,7 @@ interface IntrospectionResult {
   warnings: string[];
 }
 
-export function IntrospectionPanel({ filePath, onClose }: IntrospectionPanelProps) {
+export function IntrospectionPanel({ filePath, studyId, onClose }: IntrospectionPanelProps) {
   const [result, setResult] = useState<IntrospectionResult | null>(null);
   const [isLoading, setIsLoading] = useState(false);
   const [error, setError] = useState<string | null>(null);
@@ -73,21 +74,37 @@ export function IntrospectionPanel({ filePath, onClose }: IntrospectionPanelProp
     setIsLoading(true);
     setError(null);
     try {
-      const res = await fetch('/api/nx/introspect', {
-        method: 'POST',
-        headers: { 'Content-Type': 'application/json' },
-        body: JSON.stringify({ file_path: filePath }),
-      });
-      if (!res.ok) throw new Error('Introspection failed');
+      let res;
+      
+      // If we have a studyId, use the study-aware introspection endpoint
+      if (studyId) {
+        // Don't encode studyId - it may contain slashes for nested paths (e.g., M1_Mirror/study_name)
+        res = await fetch(`/api/optimization/studies/${studyId}/nx/introspect`);
+      } else {
+        // Fallback to direct path introspection
+        res = await fetch('/api/nx/introspect', {
+          method: 'POST',
+          headers: { 'Content-Type': 'application/json' },
+          body: JSON.stringify({ file_path: filePath }),
+        });
+      }
+      
+      if (!res.ok) {
+        const errData = await res.json().catch(() => ({}));
+        throw new Error(errData.detail || 'Introspection failed');
+      }
       const data = await res.json();
-      setResult(data);
+      
+      // Handle different response formats
+      setResult(data.introspection || data);
     } catch (e) {
-      setError('Failed to introspect model');
-      console.error(e);
+      const msg = e instanceof Error ? e.message : 'Failed to introspect model';
+      setError(msg);
+      console.error('Introspection error:', e);
     } finally {
       setIsLoading(false);
     }
-  }, [filePath]);
+  }, [filePath, studyId]);
 
   useEffect(() => {
     runIntrospection();