feat: backend FastAPI funcional con auth, ETA y simulador

backend/database.py

@@ -0,0 +1,16 @@
+from sqlalchemy import create_engine
+from sqlalchemy.ext.declarative import declarative_base
+from sqlalchemy.orm import sessionmaker
+
+DATABASE_URL = "postgresql://postgres:postgres@localhost:5432/hackonlinces"
+
+engine = create_engine(DATABASE_URL)
+SessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine)
+Base = declarative_base()
+
+def get_db():
+    db = SessionLocal()
+    try:
+        yield db
+    finally:
+        db.close()