Fix: Add python-multipart package required for document uploading

Fix: Add serverless-friendly opencv-python-headless dependency

Fix: Add pytesseract package wrapper

Fix: Add scikit-learn dependency required by document classifier

Fix: Hard removed hidden UTF-8 BOM from requirements

Build: Stripped heavy local AI packages for serverless compatibility

Fix: Ignore pywin32 on Linux environments

Force clean UTF-8 without BOM

Fix requirements.txt encoding

Initial commit