Method not found IChatClient.get_Metadata()

[freastro]

The CustomerSupport project compiles but fails with a runtime exception with .NET 8.0.411 on Windows 11:

Unhandled exception. System.MissingMethodException: Method not found: 'Microsoft.Extensions.AI.ChatClientMetadata Microsoft.Extensions.AI.IChatClient.get_Metadata()'.
   at Program.<Main>$(String[] args)
   at System.Runtime.CompilerServices.AsyncMethodBuilderCore.Start[TStateMachine](TStateMachine& stateMachine)
   at Program.<Main>$(String[] args)
   at Program.<Main>(String[] args)