Detach emulators from launching shell

README.md

@@ -131,6 +131,12 @@ starts on software rendering as it always did. None of this is essential.
 would leave the machine short, printing what is attached, what is large, and
 what usually frees enough. `EMU_FORCE=1` overrides it.
 
+The emulator is launched in its own session with stdin closed, so it outlives
+both an interactive terminal and an isolated command runner. A bare background
+job appeared to work from long-lived agent shells but was shut down as soon as
+a one-command execution session ended; the emulator's own log showed a clean
+shutdown after boot rather than a crash.
+
 The reason is a real incident rather than tidiness. On 2026-08-30 an emulator
 was started on this box with 2.8 GB available; the OOM killer ran, and what
 it took was not the emulator that had just started — it walked the user slice