refactor: simplify cookie handling in middleware

- Updated LanguageMiddleware and UserIdentityMiddleware to always set cookies for language and user ID, respectively, removing conditional checks for existing cookies. This streamlines the cookie management process and ensures consistent behavior across sessions.

app.py

@@ -88,8 +88,7 @@ class LanguageMiddleware(BaseHTTPMiddleware):
         # Continue processing the request
         response = await call_next(request)
         
-        # Set cookie if it's not already set or if it's different
+        # Set cookie
-        if not request.cookies.get("lang") or request.cookies.get("lang") != lang:
         response.set_cookie(
             key="lang",
             value=lang,
@@ -129,11 +128,11 @@ class UserIdentityMiddleware(BaseHTTPMiddleware):
         response = await call_next(request)
         
         # Set cookie if it's not already set
-        if not request.cookies.get("user_id"):
+
         response.set_cookie(
             key="user_id",
             value=user_id,
-                max_age=None,  # Cookie will never expire
+            max_age=365 * 24 * 60 * 60,  # 1 year
             httponly=True,
             samesite="lax"
         )

database.py

@@ -54,7 +54,7 @@ def new_user() -> int:
             user = User()
             user.last_seen = user.created_at = datetime.now(UTC)
             db.add(user)
-            db.flush()
+            db.commit()
             return user.id
     finally:
         db.close()