The fresh reap-coordination maps still used legacy `.uid` tuples even
though process monitors and channels carry complete `Aid` identities.
This extended the legacy key format into new private state.
Key both reap maps by `Aid` and derive `.uid` only when accessing the
existing `_children` map. UUID-based `Aid` hashing lets the subactor
and decoded channel identities resolve the same synchronization state.
Update registration tests to exercise the full identity keys.
Review: PR #481 (goodboy)
https://github.com/goodboy/tractor/pull/481#pullrequestreview-5012942328
Prompt-IO: ai/prompt-io/opencode/20260824T233957Z_5327b25e_prompt_io.md
(this patch was generated in some part by `opencode` using `gpt-5.6-sol` (`openai`))
Gud Boi