fix: Add missing update_cumulative_file method to CumulativeMarkdownManager

The method was being called by multiple scripts but didn't exist, causing Instagram
capture to fail at post 1200. Added a compatibility method that uses a basic
formatter to handle any source type with standard fields like ID, title, views,
likes, images, etc.

Tested successfully with test script.

src/cumulative_markdown_manager.py

@@ -270,4 +270,105 @@ class CumulativeMarkdownManager:
             'file_size_kb': file_path.stat().st_size // 1024
         }
         
-        return stats
+        return stats
+    
+    def update_cumulative_file(self, items: List[Dict[str, Any]], source_name: str) -> Path:
+        """
+        Update cumulative file for a source using a basic formatter.
+        This is a compatibility method for scripts that expect this interface.
+        """
+        def basic_formatter(items: List[Dict[str, Any]]) -> str:
+            """Basic markdown formatter for any source."""
+            sections = []
+            
+            for item in items:
+                section = []
+                
+                # ID
+                item_id = item.get('id', 'Unknown')
+                section.append(f"# ID: {item_id}")
+                section.append("")
+                
+                # Title
+                title = item.get('title', item.get('caption', 'Untitled'))
+                if title:
+                    # Truncate very long titles/captions
+                    if len(title) > 100:
+                        title = title[:97] + "..."
+                    section.append(f"## Title: {title}")
+                    section.append("")
+                
+                # Type
+                item_type = item.get('type', source_name.lower())
+                section.append(f"## Type: {item_type}")
+                section.append("")
+                
+                # Link
+                link = item.get('link', item.get('url', ''))
+                if link:
+                    section.append(f"## Link: {link}")
+                    section.append("")
+                
+                # Author/Channel
+                author = item.get('author', item.get('channel', ''))
+                if author:
+                    section.append(f"## Author: {author}")
+                    section.append("")
+                
+                # Publish Date
+                pub_date = item.get('publish_date', item.get('published', ''))
+                if pub_date:
+                    section.append(f"## Publish Date: {pub_date}")
+                    section.append("")
+                
+                # Views
+                views = item.get('views')
+                if views is not None:
+                    section.append(f"## Views: {views:,}")
+                    section.append("")
+                
+                # Likes
+                likes = item.get('likes')
+                if likes is not None:
+                    section.append(f"## Likes: {likes:,}")
+                    section.append("")
+                
+                # Comments
+                comments = item.get('comments')
+                if comments is not None:
+                    section.append(f"## Comments: {comments:,}")
+                    section.append("")
+                
+                # Local images
+                local_images = item.get('local_images', [])
+                if local_images:
+                    section.append(f"## Images Downloaded: {len(local_images)}")
+                    for i, img_path in enumerate(local_images, 1):
+                        rel_path = Path(img_path).relative_to(self.config.data_dir)
+                        section.append(f"![Image {i}]({rel_path})")
+                    section.append("")
+                
+                # Local thumbnail
+                local_thumbnail = item.get('local_thumbnail')
+                if local_thumbnail:
+                    section.append("## Thumbnail:")
+                    rel_path = Path(local_thumbnail).relative_to(self.config.data_dir)
+                    section.append(f"![Thumbnail]({rel_path})")
+                    section.append("")
+                
+                # Description/Caption
+                description = item.get('description', item.get('caption', ''))
+                if description:
+                    section.append("## Description:")
+                    section.append(description)
+                    section.append("")
+                
+                # Separator
+                section.append("-" * 50)
+                section.append("")
+                
+                sections.append('\n'.join(section))
+            
+            return '\n'.join(sections)
+        
+        return self.save_cumulative(items, basic_formatter)

test_cumulative_fix.py

@@ -0,0 +1,67 @@
+#!/usr/bin/env python3
+"""
+Test the CumulativeMarkdownManager fix.
+"""
+
+import sys
+from pathlib import Path
+sys.path.insert(0, str(Path(__file__).parent))
+
+from src.cumulative_markdown_manager import CumulativeMarkdownManager
+from src.base_scraper import ScraperConfig
+
+def test_cumulative_manager():
+    """Test that the update_cumulative_file method works."""
+    print("Testing CumulativeMarkdownManager fix...")
+    
+    # Create test config
+    config = ScraperConfig(
+        source_name='TestSource',
+        brand_name='hkia',
+        data_dir=Path('test_data'),
+        logs_dir=Path('test_logs'),
+        timezone='America/Halifax'
+    )
+    
+    # Create manager
+    manager = CumulativeMarkdownManager(config)
+    
+    # Test data
+    test_items = [
+        {
+            'id': 'test123',
+            'title': 'Test Post',
+            'type': 'test',
+            'link': 'https://example.com/test123',
+            'author': 'test_user',
+            'publish_date': '2025-08-19',
+            'views': 1000,
+            'likes': 50,
+            'comments': 10,
+            'local_images': ['test_data/media/test_image.jpg'],
+            'description': 'This is a test post'
+        }
+    ]
+    
+    try:
+        # This should work now
+        output_file = manager.update_cumulative_file(test_items, 'TestSource')
+        print(f"✅ Success! Created file: {output_file}")
+        
+        # Check that the file exists and has content
+        if output_file.exists():
+            content = output_file.read_text()
+            print(f"✅ File has {len(content)} characters")
+            print(f"✅ Contains ID section: {'# ID: test123' in content}")
+            return True
+        else:
+            print("❌ File was not created")
+            return False
+            
+    except Exception as e:
+        print(f"❌ Error: {e}")
+        return False
+
+if __name__ == "__main__":
+    success = test_cumulative_manager()
+    sys.exit(0 if success else 1)