workmanager 0.5.2 references the removed PluginRegistrantCallback and
other V1 Flutter embedding APIs, causing a Kotlin compilation failure
when building the release AAB with AGP 8.11.1 / Kotlin 2.2.20.
0.9.x uses only V2 embedding. API migration: ExistingWorkPolicy →
ExistingPeriodicWorkPolicy for registerPeriodicTask.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>