feat: setup barrelsby for automatic barrel file generation

Add barrelsby as a dev dependency with a `generate-barrels` npm script and a `barrelesby.json` config targeting `./src`. This automates creation of barrel/index files to simplify imports across the project.

src/data/models/user/index.ts

@@ -0,0 +1,9 @@
+// user 子目录 barrel export
+export { AvatarData } from "./avatar_data";
+export { CreditsData } from "./credits_data";
+export { CreditsHistoryData } from "./credits_history_data";
+export { PersonalityTraits } from "./personality_traits";
+export { RecentMemory } from "./recent_memory";
+export { UpdateProfileRequest } from "./update_profile_request";
+export { User } from "./user";
+export { UserStatsResponse } from "./user_stats_response";