Agent Skills: cron-model-migration

Safely change models for OpenClaw cron jobs without leaving behind session/model mismatch errors. Use when creating or editing cron jobs with `payload.model`, when moving a job between models/providers, when diagnosing `LiveSessionModelSwitchError`, or when deciding whether a cron should run in `sessionTarget: "isolated"`, `"current"`, `"main"`, or a custom persistent session.