feat: enhance canvas and node components with improved edge handling and new node features

- Refactored canvas toolbar to utilize new canvas placement context for node creation.
- Updated node components (compare, group, image, note, prompt, text) to include source and target handles for better edge management.
- Improved edge intersection handling during node drag operations for enhanced user experience.
- Added utility functions for edge identification and node positioning to streamline interactions.

components/canvas/nodes/text-node.tsx

@@ -75,7 +75,13 @@ export default function TextNode({ id, data, selected }: NodeProps<TextNode>) {
   );
 
   return (
-    <BaseNodeWrapper selected={selected} status={data._status}>
+    <BaseNodeWrapper selected={selected} status={data._status} className="relative">
+      <Handle
+        type="target"
+        position={Position.Left}
+        className="!h-3 !w-3 !bg-primary !border-2 !border-background"
+      />
+
       <div className="w-64 p-3">
         <div className="text-xs font-medium text-muted-foreground mb-1">
           📝 Text