fix: persist avatar data and uploads

digital-avatar-app/backend/database.py

@@ -5,10 +5,11 @@ from sqlalchemy.orm import sessionmaker, declarative_base, Session
 
 BASE_DIR = os.path.dirname(os.path.abspath(__file__))
 DB_FILE = os.path.join(BASE_DIR, "avatar.db")
+DATABASE_URL = os.getenv("DATABASE_URL", f"sqlite:///{DB_FILE}")
 
 engine = create_engine(
-    f"sqlite:///{DB_FILE}",
-    connect_args={"check_same_thread": False},
+    DATABASE_URL,
+    connect_args={"check_same_thread": False} if DATABASE_URL.startswith("sqlite:") else {},
 )
 SessionLocal = sessionmaker(bind=engine, autoflush=False, expire_on_commit=False)
 Base = declarative_base()

digital-avatar-app/backend/routers/knowledge.py

@@ -15,7 +15,7 @@ import embeddings
 router = APIRouter()
 
 BASE_DIR = os.path.dirname(os.path.abspath(__file__))
-UPLOAD_DIR = os.path.join(BASE_DIR, "uploads")
+UPLOAD_DIR = os.path.abspath(os.getenv("UPLOAD_DIR", os.path.join(BASE_DIR, "uploads")))
 os.makedirs(UPLOAD_DIR, exist_ok=True)
 
 ALLOWED_EXT = {".md", ".txt", ".pdf", ".doc", ".docx", ".xlsx"}