Comprehensive cache directory environment variable fix

- Add XDG_CACHE_HOME and HUGGINGFACE_HUB_CACHE environment variables
- Add TOKENIZERS_PARALLELISM=false to prevent threading issues
- Cover all possible cache directory paths used by transformers
- Fix persistent Permission denied: /.cache errors

highlights_api.py

@@ -13,6 +13,9 @@ os.environ['HF_HOME'] = CACHE_DIR
 os.environ['TRANSFORMERS_CACHE'] = CACHE_DIR
 os.environ['HF_DATASETS_CACHE'] = CACHE_DIR
 os.environ['TORCH_HOME'] = CACHE_DIR
+os.environ['XDG_CACHE_HOME'] = CACHE_DIR
+os.environ['HUGGINGFACE_HUB_CACHE'] = CACHE_DIR
+os.environ['TOKENIZERS_PARALLELISM'] = 'false'
 
 from fastapi import FastAPI, UploadFile, File, HTTPException, BackgroundTasks
 from fastapi.responses import FileResponse, JSONResponse

src/smolvlm2_handler.py

@@ -14,6 +14,9 @@ if 'HF_HOME' not in os.environ:
     os.environ['TRANSFORMERS_CACHE'] = CACHE_DIR
     os.environ['HF_DATASETS_CACHE'] = CACHE_DIR
     os.environ['TORCH_HOME'] = CACHE_DIR
+    os.environ['XDG_CACHE_HOME'] = CACHE_DIR
+    os.environ['HUGGINGFACE_HUB_CACHE'] = CACHE_DIR
+    os.environ['TOKENIZERS_PARALLELISM'] = 'false'
 
 import torch
 from transformers import AutoModelForImageTextToText, AutoProcessor