Move torch/tensorflow to optional extras to fix CI disk space

The combined size of torch, tensorflow, and NVIDIA CUDA dependencies
exceeded GitHub Actions runner disk space (~4GB+). These ML frameworks
are now available as optional extras via pip install .[torch] or
pip install .[tensorflow].

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

Author: blaiszik

requirements.txt

@@ -1,17 +1,16 @@
+# Core runtime dependencies (see setup.py)
+mdf_toolbox>=0.7.1
 globus-sdk>=3,<4
-dlhub_sdk>=2.1.0
-requests>=2.18.4
-tqdm>=4.19.4
-six>=1.11.0
-h5py>=2.10.0
-numpy>=1.15.4
-pandas>=0.23.4
-scikit-learn>=1.0
-pydantic>=2.7.2
-mdf_forge>=0.8.0
 mdf-connect-client>=0.5.0
+requests>=2.31.0
+tqdm>=4.66.0
+numpy>=2.0.0
+pandas>=2.2.2
+h5py>=3.11.0
+pydantic>=2.7.2
 json2table>=1.1.5
-torch>=1.8.0
-tensorflow>=2
-tqdm>=4.64
-openpyxl>=3.1.0
+typer>=0.12.0
+rich>=13.7.0
+
+# Optional extras are available via pip install .[name]
+# torch, tensorflow, excel, huggingface, examples, dev