Implement agent node functionality in canvas, including connection policies and UI updates. Add support for agent node type in node catalog, templates, and connection validation. Update documentation to reflect new agent capabilities and ensure proper handling of input sources. Enhance adjustment preview to include crop node. Add tests for agent connection policies.

components/canvas/nodes/base-node-wrapper.tsx

@@ -45,6 +45,7 @@ const RESIZE_CONFIGS: Record<string, ResizeConfig> = {
   "detail-adjust": { minWidth: 300, minHeight: 820 },
   crop: { minWidth: 320, minHeight: 520 },
   render: { minWidth: 260, minHeight: 300, keepAspectRatio: true },
+  agent: { minWidth: 300, minHeight: 280 },
   text: { minWidth: 220, minHeight: 90 },
   note: { minWidth: 200, minHeight: 90 },
 };