fix: Switch to SQLite for cloud deployment

Dockerfile

@@ -6,6 +6,7 @@ RUN npm install
 COPY frontend/ .
 # Set API base to empty so it uses relative paths (handled by Nginx)
 ENV NEXT_PUBLIC_API_BASE=""
+ENV DATABASE_URL="sqlite:///./andesops.db"
 RUN npm run build
 
 # Final Image

backend/app/database.py

@@ -3,10 +3,13 @@ from sqlalchemy.ext.declarative import declarative_base
 from sqlalchemy.orm import sessionmaker
 from app.config import settings
 
-SQLALCHEMY_DATABASE_URL = settings.database_url or "mysql+pymysql://root:@localhost/andesai_db"
+SQLALCHEMY_DATABASE_URL = settings.database_url or "sqlite:///./andesops.db"
+
+# SQLite specific config for FastAPI multi-threading
+connect_args = {"check_same_thread": False} if SQLALCHEMY_DATABASE_URL.startswith("sqlite") else {}
 
 engine = create_engine(
-    SQLALCHEMY_DATABASE_URL
+    SQLALCHEMY_DATABASE_URL, connect_args=connect_args
 )
 SessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine)