Jumoo.Processing: v19 beta01

Jumoo.Processing: v19/main branched from v18/main for the Umbraco 19 upgrade
Moved to .NET 11 (RC3 SDK) and Umbraco 19.0.0-beta1; runtime async turned on to match Umbraco
SignalR hub now connects with the backoffice cookie (Umbraco 19 dropped the client-side token); startHub(token, methods) deprecated in favour of startHub(methods)
Pipeline create/update/process calls wait for re-login after a session timeout and retry, instead of the run dropping back to waiting
Removed IPipelineProcessor.Create(string); Create(strategy, options) now on the interface, IPipelineOptionsProcessor deprecated
release.yml: installs the pinned SDK before GitVersion, which failed the first beta01 tag run
Fixed the missing Step label in the error modal on v17/main, forward-ported to v18 and v19
Released 19.0.0-beta01 to NuGet and npm (next-19)