DIBP Topic 聚类

Use when the user asks to (re)cluster DIBP topic data into 需求簇/用户主动洞察, regenerate clusters.json, review the long-tail (未分类) topics, add a new theme to the taxonomy, or push cluster results to the dev/prod backend. Covers the offline batch pipeline in scripts/cluster-*.mjs — this is NOT the daily incremental Hive job described in docs/features/dibp-insight-daily-clustering.md, which is unimplemented.

by @christinelee3025·MIT-0