Add initial files for Audio Dashboard Management System

- Created .env.example for environment variable configuration.
- Added docker-compose.yml for service orchestration.
- Implemented frequency response extraction in extract_frequency_response.py and convert_to_frequency_db.py.
- Generated output files: frequency_response_detailed.json, frequency_response_points.json, frequency_response.csv, and frequency_response_curve.png.
- Included sample measurement data for FiiO FA19 in CSV format.

backend/database.py

@@ -14,13 +14,15 @@ DATABASE_NAME = os.getenv("DATABASE_NAME", "audio")
 DATABASE_USER = os.getenv("DATABASE_USER", "root")
 DATABASE_PASSWORD = os.getenv("DATABASE_PASSWORD", "root123")
 
-# Create database URL (same format as working code)
+# Create database URL (only charset parameter)
 DATABASE_URL = f"mysql+pymysql://{DATABASE_USER}:{DATABASE_PASSWORD}@{DATABASE_HOST}:{DATABASE_PORT}/{DATABASE_NAME}?charset=utf8mb4"
 
-# Create engine (same config as working code)
+# Create engine with additional connection arguments
+# Use connect_args for parameters that shouldn't be in the URL
 engine = create_engine(
     DATABASE_URL,
-    echo=os.getenv("DEBUG", "False") == "True"
+    echo=os.getenv("DEBUG", "False") == "True",
+    connect_args={}
 )
 
 # Create session factory