A request sent just as the app expires an idle control connection crosses
the app's id-less idle-close notice: the client's pre-send check saw an
open connection, wrote the request, and read the notice as its reply, so
`--connect` and the MCP server failed a command the app never read.
The app reads nothing after its idle timeout, so such a request never ran.
The app now marks the notice `"closed": "idle"`, and `Remote::call` sends
a request whose reply is that notice once more on a new connection (it
also matches the notice's exact text, for apps from before the marker).
At most one resend per call, whatever the reason; a reply with an id or
any other error is returned as before.
`idle_close_reconnects_without_replaying_a_command` now forces both
orders (notice before the next request, and a request crossing it)
instead of racing the notice; with main's client it fails every run.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
