Is your feature request related to a problem? Please describe.
Currently the protocol spec states (link):

For the stdio transport, the client SHOULD initiate shutdown by:

1. First, closing the input stream to the child process (the server)
2. Waiting for the server to exit, or sending SIGTERM if the server does not exit within a reasonable time
3. Sending SIGKILL if the server does not exit within a reasonable time after SIGTERM

The server MAY initiate shutdown by closing its output stream to the client and exiting.

On Windows there are no SIGTERM and SIGKILL though.

Describe the solution you'd like
Clarify the signaling mechanism on Windows.

Describe alternatives you've considered
Not providing any signaling mechanism on windows, i.e. leave point 2 and 3 not applicable.

Additional context
-