feat: initial implementation of People Counter web app

- Add Flask application with MJPEG video streaming
- Implement OpenCV DNN face detection module
- Add zone-based entry/exit tracking with cooldown mechanism
- Create web interface with real-time WebSocket updates
- Add model download script and comprehensive README
- Include OpenCV DNN model files for face detection

.gitignore

@@ -0,0 +1,38 @@
+# Python
+__pycache__/
+*.py[cod]
+*$py.class
+*.so
+.Python
+env/
+venv/
+ENV/
+env.bak/
+venv.bak/
+*.egg-info/
+dist/
+build/
+
+# IDE
+.vscode/
+.idea/
+*.swp
+*.swo
+*~
+.cursor/
+
+# Logs
+*.log
+.cursor/debug.log
+
+# OS
+.DS_Store
+Thumbs.db
+
+# Project specific - model files are included but could be excluded if needed
+# Uncomment the line below to exclude model files from git (saves ~10MB)
+# models/*.caffemodel
+
+# Environment variables
+.env
+.env.local