Commit dc20ddec dropped the 禁止选择第一项、最近登录或最近使用账号 rule
from dws-shared/SKILL.md during the multi-skill refactor while the
MultiSkill e2e contract still asserts it there, blocking the
v1.0.55-beta.6 release run. Restore the rule as a mandatory-contract
bullet pointing at dingtalk-profile/SKILL.md for the full selection and
cross-org rules.