feat(dashboard): Enhanced chat, spec management, and Claude integration

Backend:
- spec.py: New AtomizerSpec REST API endpoints
- spec_manager.py: SpecManager service for unified config
- interview_engine.py: Study creation interview logic
- claude.py: Enhanced Claude API with context
- optimization.py: Extended optimization endpoints
- context_builder.py, session_manager.py: Improved services

Frontend:
- Chat components: Enhanced message rendering, tool call cards
- Hooks: useClaudeCode, useSpecWebSocket, improved useChat
- Pages: Updated Dashboard, Analysis, Insights, Setup, Home
- Components: ParallelCoordinatesPlot, ParetoPlot improvements
- App.tsx: Route updates for canvas/studio

Infrastructure:
- vite.config.ts: Build configuration updates
- start/stop-dashboard.bat: Script improvements

atomizer-dashboard/frontend/src/pages/Home.tsx

@@ -394,18 +394,32 @@ const Home: React.FC = () => {
                       <p className="text-dark-400 text-sm">Study Documentation</p>
                     </div>
                   </div>
-                  <button
-                    onClick={() => handleSelectStudy(selectedPreview)}
-                    className="flex items-center gap-2 px-5 py-2.5 rounded-lg transition-all font-semibold whitespace-nowrap hover:-translate-y-0.5"
-                    style={{
-                      background: 'linear-gradient(135deg, #00d4e6 0%, #0891b2 100%)',
-                      color: '#000',
-                      boxShadow: '0 4px 15px rgba(0, 212, 230, 0.3)'
-                    }}
-                  >
-                    Open
-                    <ArrowRight className="w-4 h-4" />
-                  </button>
+                  <div className="flex items-center gap-2">
+                    <button
+                      onClick={() => navigate(`/canvas/${selectedPreview.id}`)}
+                      className="flex items-center gap-2 px-4 py-2.5 rounded-lg transition-all font-medium whitespace-nowrap hover:-translate-y-0.5"
+                      style={{
+                        background: 'rgba(8, 15, 26, 0.85)',
+                        border: '1px solid rgba(0, 212, 230, 0.3)',
+                        color: '#00d4e6'
+                      }}
+                    >
+                      <Layers className="w-4 h-4" />
+                      Canvas
+                    </button>
+                    <button
+                      onClick={() => handleSelectStudy(selectedPreview)}
+                      className="flex items-center gap-2 px-5 py-2.5 rounded-lg transition-all font-semibold whitespace-nowrap hover:-translate-y-0.5"
+                      style={{
+                        background: 'linear-gradient(135deg, #00d4e6 0%, #0891b2 100%)',
+                        color: '#000',
+                        boxShadow: '0 4px 15px rgba(0, 212, 230, 0.3)'
+                      }}
+                    >
+                      Open
+                      <ArrowRight className="w-4 h-4" />
+                    </button>
+                  </div>
                 </div>
 
                 {/* Study Quick Stats */}