关于条目获取角色的 summary

/v0/subjects/{subject_id}/characters 会获取声优的 short_summary 但是没有角色的 summary，server-private 则完全没有。感觉很奇怪，可以给角色加上 summary 吗？

Start by tracing the /v0/subjects/{subject_id}/characters response and compare how character and voice-actor summaries are handled; also check the corresponding server-private behavior. Done means character entries expose their summary consistently with the requested API behavior, with coverage updated if an existing test path is found.

Written by the indexing model from the issue text.