Track successful `create=True` calls through Tractor's
current-process factory instead of scanning `/dev/shm` or trusting
the attachment cache.
- cooperate with normal actor unlink and restore token-cache state
- verify POSIX object identity before fallback cleanup
- fail after cleaning exact surviving segments
- reproduce the pre-`current_actor()` allocation leak
Prompt-IO: ai/prompt-io/opencode/20260727T215906Z_689df816_prompt_io.md
(this patch was generated in some part by `opencode` using `gpt-5.6-sol` (`openai`))
Gud Boi