- Transport.kt used the reified Json.encodeToString extension without importing kotlinx.serialization.encodeToString, so it resolved to the two-argument member overload and failed to compile. - Opt in to ExperimentalMaterial3Api for the clickable game tile. - Drop --stacktrace from the CI build. A one-line Kotlin error was being buried under 150 lines of Gradle internals, which made the actual message hard to find in the log. Co-Authored-By: Claude Opus 5 <[email protected]> Claude-Session: https://claude.ai/code/session_015qjfMiPUDshdKEUa6vxqzN