feat(core-api): compose @repo/auth/api into appRouter under 'auth' namespace

packages/blog/src/index.ts

@@ -1,3 +1,4 @@
 export type { Article, ArticleStatus } from "./entities/article";
+export type { BlogRouter } from "./integrations/api/router";
 export { ArticleNotFoundError, InputParseError } from "./entities/errors";
 export { articleBySlugQuery, listArticlesQuery } from "./ui/query";