docs(ci): correct the ios hang wording and note the device lock

.github/scripts/folio-run.sh

@@ -31,7 +31,9 @@ case "$platform" in
     # freshly installed app IS clear state). The in-run reinstall path is worth
     # avoiding here: `simctl uninstall` + `install` immediately followed by the
     # XCTest runner's own launch hits "app.folio is unknown to FrontBoard"
-    # perhaps half the time, and the run then hangs rather than failing.
+    # perhaps half the time. The launch RPC is bounded now, so that surfaces
+    # as an error rather than an indefinite hang, but a failed leg is still a
+    # failed leg and a fresh install is already clear state.
     folio_args+=(--platform ios
       --clear-data=false
       --ios-device "${IOS_DEVICE:-iPhone 16 Pro}")

docs/development/ci.md

@@ -61,8 +61,15 @@ The ios leg passes `--clear-data=false`, because the job installs a fresh build
 immediately before the run and a freshly installed app is already clear state.
 The in-run reinstall is worth avoiding: `simctl uninstall` + `install` followed
 straight away by the XCTest runner's own launch fails with `app.folio is unknown
-to FrontBoard` maybe half the time, and the run then hangs rather than failing.
-The job timeouts are the backstop if it happens anyway.
+to FrontBoard` maybe half the time. That used to hang the run outright; the
+launch RPC is bounded now, so it fails in about 90 seconds with a real error
+instead, but a failing leg is still a failing leg. The job timeouts are the
+backstop if it happens anyway.
+
+Only one sanderling run may drive a given simulator at a time. The driver takes
+an advisory lock on the target's UDID and a second run is refused with the lock
+path in the message, because two runs interleaving app lifecycle leave the first
+run's automation session bound to a bundle the simulator no longer knows.
 
 ## replay-ui