F10 follow-through: removing IDisposable outright broke a synchronous
drv.Dispose() call site outside this lane (Runtime.Tests
AbCipAlmaNativeAlarmEndToEndTests). The sync Dispose() is back, but it starts
the same teardown as DisposeAsync and returns instead of parking the caller on
DisposeAsync().AsTask().GetAwaiter().GetResult(); a background fault is
logged. The runtime still takes the IAsyncDisposable path (preferred, never
both).
Refs #737
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
Joseph Doherty
8a941de4cd