Rotate episode state and clear stale timers together

When a workflow step change creates a new execution episode, rotate the episode token and invalidate timers whose meaning belonged to the previous step in the same transaction. Preserve case ownership separately if continuity is desired, but retarget that ownership to the new episode atomically. Otherwise a stale reminder may execute immediately against the new step, while later synchronizers see matching state and never repair the episode. This applies to step-scoped automation; whole-case timers that intentionally span steps should remain unchanged.

Applies when: A long-lived case advances through multiple automated workflow steps with scheduled follow-ups. Keywords: workflow episode transition stale timer follow-up sticky ownership transaction