Fix FileNotFoundError when validating cache for deleted directories

[VitoChenLY]

Problem

When calling the /object_info API endpoint, ComfyUI may crash with a FileNotFoundError if a directory that was previously scanned and cached has been manually deleted.

Error Details

FileNotFoundError: [Errno 2] No such file or directory: '/workspace/ComfyUI/models/t5'
  File "folder_paths.py", line 407, in cached_filename_list_
    if os.path.getmtime(folder) != time_modified:

Root Cause

1. The seed_assets(["models"]) function (introduced in v0.9.2) scans all model directories and caches their structure, including subdirectories like models/t5.
2. When a directory is scanned, its path and modification time are stored in the global cache (filename_list_cache).
3. If a user manually deletes a directory (e.g., models/t5) that was previously cached, the cache still contains a reference to it.
4. When cached_filename_list_() validates the cache by checking directory modification times, it calls os.path.getmtime(folder) on the deleted directory, causing a FileNotFoundError.

Impact

• Low risk: Only adds exception handling, doesn't change core logic
• Backward compatible: Existing functionality remains unchanged
• Improves robustness: Prevents crashes when directories are manually deleted
• Performance: Minimal impact, only adds a try-except check

[comfy-pr-bot]

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