Upgrade transformers to 5.5.3 and refactor hf_transformers_utils into subpackage (#21569)

python/pyproject_cpu.toml

@@ -31,6 +31,7 @@ dependencies = [
   "llguidance>=0.7.11,<0.8.0",
   "modelscope",
   "msgspec",
+  "easydict",
   "ninja",
   "numpy",
   "openai-harmony==0.0.4",
@@ -60,8 +61,8 @@ dependencies = [
   "torchaudio==2.9.0",
   "torchvision==0.24.0",
   "tqdm",
-  "mistral_common>=1.9.0",
-  "transformers==5.3.0",
+  "mistral_common>=1.11.0",
+  "transformers==5.5.4",
   "triton==3.5.0",
   "uvicorn",
   "uvloop",