fix(lifecycle): on Windows, CTRL_CLOSE kills Nvim mid-teardown

Problem:
`signal_ignore_deadly` doesn't work for Windows, where the console still
may terminate Nvim during teardown (after `signal_teardown`), while it
is already trying to exit. Besides interrupting any housekeeping we are
doing, it results in an unpredictable exit code (flaky tests).

    [Process exited -1073741510]  // 0xC000013A STATUS_CONTROL_C_EXIT

Solution:
Register our own CTRL_CLOSE_EVENT handler which "blocks" the signal.
Note: if exit takes longer than 5s, Windows will consider the process
"hung" and kill it anyway.

0 files changed, 0 insertions, 0 deletions