Jobs don't stay alive for JobSend

This may be related to #1102, but I'm having trouble understanding how to use the JobSend function in plugins, if it is even possible. It seems possible to start jobs, and receive messages from them, but jobs that await info from stdin do not seem to stay alive long enough to do so.

Here's a minimal example that illustrates the problem. Suppose this is my init.lua:

function JobExit()
    messenger:AddLog("job stopped")
end

function JobErr(s)
    messenger:AddLog("stderr:" .. s)
end

function JobOut(s)
    messenger:AddLog("stdout:" .. s)
end

function testJob()
    testJ = JobStart('cat',
        'init.JobOut',
        'init.JobErr',
        'init.JobExit'
    )
    messenger:AddLog("job started")
    JobSend(testJ, "hello world")
end

function onViewOpen(view)
    testJob()
end

Expected outcome in the log:

job started
stdout:hello world

Actual outcome:

job started
job stopped

The process just dies immediately. Of course, cat from the command line without input would not do this. Indeed, I cannot find a way to keep any job "alive" long enough to use JobSend at all. (And it's the same using JobSpawn instead of JobStart.)

I might just be missing something obvious. If so, my apologies.

Maybe this isn't the place to mention it, but I just wanted to note in passing that I love micro overall, even with these little hiccups. I've been looking for a simple, lightweight but extensible, modern and non-weird-and-vi-ish terminal editor for so long that I had almost given up. Such a wonderful thing to see.

Specifications

Commit hash: 2c219ba
OS: ArchLinux x86_64
Terminal: Kitty

Start by reproducing the minimal init.lua example with JobStart, JobSend, and then JobSpawn, observing the job and callback logs. Trace the plugin job entry points for those functions and determine why the process exits before stdin is consumed; done means a job waiting for stdin remains alive and produces the expected stdout and exit behavior.