Fold the endeavour's resolution into the plan doc + log the
session per prompt-io policy,
- `ria_nursery_removal_plan.md`: RESOLVED section — migrate
everything, remove the API; the migration-pattern table
(blocking / fire-and-forget / fan-out / collect-don't-cancel
/ mutual-rendezvous), the semantic deltas (cancel-on-first +
`collapse_eg()` chain collapse vs the old teardown-reap BEG),
the excision inventory and the structural dissolution of the
reap-hang class.
- adds the `to_actor.open_one_shot()` follow-up sketch: an
`@acm` + private task-nursery over the existing blocking
`run()` — done-`trio.Event` as a result memo (NOT a
cancel-relay), no `Portal` in the iface, errors always
propagate at scope exit; zero `_supervise` coupling.
- prompt-io entry `20260706T172818Z_ad42871e` (+ raw diff-ref
companion) covering commits `d01a2123..ad42871e`.
(this patch was generated in some part by [`claude-code`][claude-code-gh])
[claude-code-gh]: https://github.com/anthropics/claude-code