process-daemon: event-driven waiting on Windows #60275

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Describe the enhancement you want to request

On Windows, packages/process-daemon still polls:

• The daemon main loop's Listener::wait is a stub that sleeps up to 25 ms (POLL_INTERVAL in src/transport/windows.rs), and Wake::notify is a no-op. That's about 40 wakeups/s when the daemon is idle.
• Each live terminal checks whether its root process has exited every 25 ms (EXIT_POLL_INTERVAL in src/service/windows.rs), which adds about 40 wakeups/s per terminal.

Unix moved to event-driven waiting in #59701, following anomalyco/opencode-pty#25. #59702 shortened the Windows poll to 25 ms as a stopgap.

Proposed approach:

1. Main loop: back Wake with an auto-reset event (CreateEventW, signalled with SetEvent). Listener::wait then calls WaitForMultipleObjects on the wake event plus the pending ConnectNamedPipe overlapped event, using the real timeout. This also lets the shared missed-wake detector run on Windows.
2. Root-process exit: replace the per-terminal poll with a blocking WaitForSingleObject on the process handle, or use RegisterWaitForSingleObject so a single thread-pool wait handles every terminal.