Add confidence breakdown display

- Shows High/Medium/Low count breakdown
- Helps verify all matching posts will be processed
- Example output:
  Filtered to 328 proposals (confidence >= Medium)
    Breakdown: High=293, Medium=35, Low=0

Co-authored-by: Qwen-Coder <qwen-coder@alibabacloud.com>

src/seo/category_manager.py

@@ -381,6 +381,12 @@ class CategoryAssignmentProcessor:
                 if confidence_order.get(p.get('category_confidence', 'Medium'), 2) >= min_confidence
             ]
             logger.info(f"Filtered to {len(filtered_proposals)} proposals (confidence >= {confidence_threshold})")
+            
+            # Show breakdown
+            high_count = sum(1 for p in filtered_proposals if p.get('category_confidence') == 'High')
+            medium_count = sum(1 for p in filtered_proposals if p.get('category_confidence') == 'Medium')
+            low_count = sum(1 for p in filtered_proposals if p.get('category_confidence') == 'Low')
+            logger.info(f"  Breakdown: High={high_count}, Medium={medium_count}, Low={low_count}")
         
         # Fetch existing categories
         self.category_manager.fetch_categories(site_name)