Add support for loading images from file paths

Introduces a backend API endpoint to load images from local file paths and return them as base64-encoded PNGs. Updates CanvasLayers.js to detect image file paths in the clipboard, validate them, and attempt to load images using multiple strategies, including the new backend endpoint, ComfyUI view endpoints, and a file picker fallback. Also updates canvas context creation to use the 'willReadFrequently' option for improved performance.

canvas_node.py

@@ -471,6 +471,70 @@ class CanvasNode:
                     'error': str(e)
                 }, status=500)
 
+        @PromptServer.instance.routes.post("/ycnode/load_image_from_path")
+        async def load_image_from_path_route(request):
+            try:
+                data = await request.json()
+                file_path = data.get('file_path')
+                
+                if not file_path:
+                    return web.json_response({
+                        'success': False,
+                        'error': 'file_path is required'
+                    }, status=400)
+                
+                log_info(f"Attempting to load image from path: {file_path}")
+                
+                # Check if file exists and is accessible
+                if not os.path.exists(file_path):
+                    log_warn(f"File not found: {file_path}")
+                    return web.json_response({
+                        'success': False,
+                        'error': f'File not found: {file_path}'
+                    }, status=404)
+                
+                # Check if it's an image file
+                valid_extensions = ('.png', '.jpg', '.jpeg', '.gif', '.bmp', '.webp', '.tiff', '.tif', '.ico', '.avif')
+                if not file_path.lower().endswith(valid_extensions):
+                    return web.json_response({
+                        'success': False,
+                        'error': f'Invalid image file extension. Supported: {valid_extensions}'
+                    }, status=400)
+                
+                # Try to load and convert the image
+                try:
+                    with Image.open(file_path) as img:
+                        # Convert to RGB if necessary
+                        if img.mode != 'RGB':
+                            img = img.convert('RGB')
+                        
+                        # Convert to base64
+                        buffered = io.BytesIO()
+                        img.save(buffered, format="PNG")
+                        img_str = base64.b64encode(buffered.getvalue()).decode('utf-8')
+                        
+                        log_info(f"Successfully loaded image from path: {file_path}")
+                        return web.json_response({
+                            'success': True,
+                            'image_data': f"data:image/png;base64,{img_str}",
+                            'width': img.width,
+                            'height': img.height
+                        })
+                        
+                except Exception as img_error:
+                    log_error(f"Error processing image file {file_path}: {str(img_error)}")
+                    return web.json_response({
+                        'success': False,
+                        'error': f'Error processing image file: {str(img_error)}'
+                    }, status=500)
+                    
+            except Exception as e:
+                log_error(f"Error in load_image_from_path_route: {str(e)}")
+                return web.json_response({
+                    'success': False,
+                    'error': str(e)
+                }, status=500)
+
     def store_image(self, image_data):
 
         if isinstance(image_data, str) and image_data.startswith('data:image'):