Widen the #70773 fix beyond the three in-request cleanup sites removed in
the cherry-picked commit: every remaining path that swaps out the shared
OpenAI client could still hard-close its pool from a thread that doesn't
own the in-flight sockets (credential rotation/refresh on the turn thread,
dead-connection cleanup, gateway cache eviction, transport recovery) —
the same FD-recycle corruption vector, just rarer.
Add AIAgent._retire_shared_openai_client(): shutdown(SHUT_RDWR) all pooled
sockets (FD-safe from any thread, unblocks in-flight readers) but never
call client.close() — FD release is deferred to GC, which cannot run until
every borrowing thread has unwound its SSL BIO. Refcounting is the
ownership handshake; with no borrowers the FDs are released immediately.
Wired into:
- _replace_primary_openai_client (rotation/refresh/dead-conn cleanup)
- try_recover_primary_transport (primary_recovery)
- release_clients (gateway cache_evict)
agent.close() keeps the hard close: full teardown is a real session
boundary where no request may be in flight.
Tests: new tests/run_agent/test_70773_shared_client_fd_corruption.py
covers the three watchdog/retry sites plus retire semantics; existing
close-assertions updated to pin retire-not-close.
1608a46884