On Windows every Hermes process (gateway, serve, TUI/slash workers, MCP
servers, CLI commands) writes the shared rotating logs through
concurrent-log-handler's cross-process rotation lock. When the emitting
thread is an asyncio event loop, a lock wait blocks the loop — stalling it
for seconds and dropping WebSocket clients (the 'gateway keeps going down'
symptom seen in #58265).
Route every file handler through a single QueueListener on a dedicated
thread: loggers only enqueue (non-blocking); the listener does the file I/O
and rotation-lock wait off the hot path. The QueueHandler funnels via the
root logger; per-handler levels and component filters are preserved by
respect_handler_level + handler.handle on the listener thread. An atexit
hook stops the listener before logging.shutdown closes the file handlers.
- _NonFormattingQueueHandler passes the raw record (in-process queue) so
target handlers apply their own RedactingFormatter/filters.
- flush_log_queue() drains synchronously (shutdown + tests).
- rotating_file_handlers() exposes the handlers now behind the listener;
tests updated to use it.
Extends the #58265 fix: the provider-key warn-storm was one amplifier of
this contention; this takes the contention off the event loop entirely.
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