feat(api): Support specifying app version for chat

api/app/repositories/app_repository.py

@@ -61,3 +61,15 @@ def get_apps_by_id(db: Session, app_id: uuid.UUID) -> App:
     """根据工作空间ID查询应用"""
     repo = AppRepository(db)
     return repo.get_apps_by_id(app_id)
+
+
+def get_release_by_version(db: Session, app_id: uuid.UUID, version: int):
+    """根据版本号查询发布快照（仅返回激活状态）"""
+    from app.models.app_release_model import AppRelease
+    return db.scalars(
+        select(AppRelease).where(
+            AppRelease.app_id == app_id,
+            AppRelease.version == version,
+            AppRelease.is_active.is_(True),
+        )
+    ).first()