First windows-latest run proved the design premise in miniature: identify
answered pid 616 while Popen.pid said 8000 — uv's Windows python.exe is a
trampoline that spawns the real interpreter as a child, so the spawner's
PID view is wrong and the process's self-declaration is right. Assert
against the child's printed os.getpid(); use taskkill /T for teardown.
Real child process binding the real pipe via the proactor loop with the
default handlers; real sync client; real collect_fleet_versions consumer;
kill-and-fallback proof. Skipped everywhere except a real Windows host.
Teknium