Add initial implementation of CalMiner with project structure, environment setup, and core features

- Create .env.example for environment variables
- Update README with project structure and development setup instructions
- Implement FastAPI application with API routes for scenarios and parameters
- Add database models for scenarios, parameters, and simulation results
- Introduce validation middleware for JSON requests
- Create services for running simulations and generating reports
- Add testing strategy and directory structure in documentation

models/parameters.py

@@ -0,0 +1,17 @@
+from sqlalchemy import Column, Integer, String, Float, ForeignKey
+from sqlalchemy.orm import relationship
+from config.database import Base
+
+
+class Parameter(Base):
+    __tablename__ = "parameter"
+
+    id = Column(Integer, primary_key=True, index=True)
+    scenario_id = Column(Integer, ForeignKey("scenario.id"), nullable=False)
+    name = Column(String, nullable=False)
+    value = Column(Float, nullable=False)
+
+    scenario = relationship("Scenario", back_populates="parameters")
+
+    def __repr__(self):
+        return f"<Parameter id={self.id} name={self.name} value={self.value}>"