Fix null-safety issues and apply code formatting

Bug fixes:
- Add null guards for base_models_roots/embeddings_roots in backup cleanup
- Fix null-safety initialization of extra_unet_roots

Formatting:
- Apply consistent code style across Python files
- Fix line wrapping, quote consistency, and trailing commas
- Add type ignore comments for dynamic/platform-specific code

py/metadata_collector/__init__.py

@@ -4,7 +4,10 @@ import logging
 logger = logging.getLogger(__name__)
 
 # Check if running in standalone mode
-standalone_mode = os.environ.get("LORA_MANAGER_STANDALONE", "0") == "1" or os.environ.get("HF_HUB_DISABLE_TELEMETRY", "0") == "0"
+standalone_mode = (
+    os.environ.get("LORA_MANAGER_STANDALONE", "0") == "1"
+    or os.environ.get("HF_HUB_DISABLE_TELEMETRY", "0") == "0"
+)
 
 if not standalone_mode:
     from .metadata_hook import MetadataHook
@@ -13,13 +16,13 @@ if not standalone_mode:
     def init():
         # Install hooks to collect metadata during execution
         MetadataHook.install()
-        
+
         # Initialize registry
         registry = MetadataRegistry()
-        
+
         logger.info("ComfyUI Metadata Collector initialized")
-        
-    def get_metadata(prompt_id=None):
+
+    def get_metadata(prompt_id=None):  # type: ignore[no-redef]
         """Helper function to get metadata from the registry"""
         registry = MetadataRegistry()
         return registry.get_metadata(prompt_id)
@@ -27,7 +30,7 @@ else:
     # Standalone mode - provide dummy implementations
     def init():
         logger.info("ComfyUI Metadata Collector disabled in standalone mode")
-        
-    def get_metadata(prompt_id=None):
+
+    def get_metadata(prompt_id=None):  # type: ignore[no-redef]
         """Dummy implementation for standalone mode"""
         return {}