refactor(settings): Alinhar leitura das variáveis de ambiente

- Usar DB_HOST/DB_PORT/DB_USER/DB_PASSWORD/DB_NAME em vez de DATABASE_URL
- Ajustes na construção do DATABASE_URL no código

app/core/settings.py

@@ -5,9 +5,8 @@ class Settings(BaseSettings):
     google_project_id: str
     google_location: str = "us-central1"
 
-    # Database -> Retirar antes de subir para a nuvem
     db_host: str
-    db_port: int = 3306
+    db_port: int = 5432
     db_user: str
     db_password: str
     db_name: str

app/db/database.py

@@ -3,7 +3,7 @@ from sqlalchemy.orm import sessionmaker, declarative_base
 from app.core.settings import settings
 
 DATABASE_URL = (
-    f"mysql+pymysql://{settings.db_user}:"
+    f"postgresql+psycopg2://{settings.db_user}:"
     f"{settings.db_password}@"
     f"{settings.db_host}:"
     f"{settings.db_port}/"