Format code style in leann_multi_vector.py for better readability

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

apps/multimodal/vision-based-pdf-multi-vector/leann_multi_vector.py

@@ -97,7 +97,9 @@ def _natural_sort_key(name: str) -> int:
     return int(m.group()) if m else 0
 
 
-def _load_images_from_dir(pages_dir: str, recursive: bool = False) -> tuple[list[str], list[Image.Image]]:
+def _load_images_from_dir(
+    pages_dir: str, recursive: bool = False
+) -> tuple[list[str], list[Image.Image]]:
     """
     Load images from a directory.
 
@@ -137,8 +139,8 @@ def _load_images_from_dir(pages_dir: str, recursive: bool = False) -> tuple[list
         try:
             img = Image.open(filepath)
             # Convert to RGB if necessary (handles RGBA, P, etc.)
-            if img.mode != 'RGB':
-                img = img.convert('RGB')
+            if img.mode != "RGB":
+                img = img.convert("RGB")
             images.append(img)
             valid_filepaths.append(filepath)
         except Exception as e:
@@ -147,7 +149,9 @@ def _load_images_from_dir(pages_dir: str, recursive: bool = False) -> tuple[list
             continue
 
     if failed_count > 0:
-        print(f"Warning: Failed to load {failed_count} image(s) out of {len(filepaths)} total files")
+        print(
+            f"Warning: Failed to load {failed_count} image(s) out of {len(filepaths)} total files"
+        )
 
     return valid_filepaths, images