Add CardioAI project with usage instructions

- Add comprehensive README.md with setup and usage instructions
- Add .env.example template (sanitized, no real API keys)
- Add root-level .gitignore to exclude .env and generated files
- Add all project modules (dashboard, predictor)
- Add data file and requirements.txt

CardioAI/requirements.txt

@@ -0,0 +1,21 @@
+# CardioAI 项目依赖
+# 创建并激活 conda 环境:
+# conda create -n cardioenv python=3.10
+# conda activate cardioenv
+
+# 然后安装依赖:
+# pip install -r requirements.txt
+
+pandas
+openpyxl
+numpy
+scikit-learn
+xgboost
+joblib
+streamlit
+plotly
+Flask
+python-dotenv
+langchain-openai
+dashscope
+requests