A control that renders as text now says which view packs declined it

Occasionally a page shows a control as its own description — a line of text beginning StackControl { Id = , Style = … } where a layout should be. That is the portal's last resort: no registered view pack accepted the control, so it rendered the control's text, escaped. It is harmless, and it is also completely silent — nothing on that path said which packs were asked, or whether any pack had registered on that hub at all, so an operator reading the logs had nothing to start from.

Now it logs once per control type per hub, at Warning, on the MeshWeaver.Layout.Client.ViewDispatch channel:

no view map accepted StackControl ($type StackControl, skins [LayoutStackSkin]) in area Workspace
on hub mesh/memex: 3 map(s) registered [MeshWeaver.Blazor.Views:AddDefaultViews,
MeshWeaver.Blazor.EntityViews:AddEntityViews, …] — falling back to the last-resort view
(escaped HTML in the Blazor portal)

The line separates the two causes that look identical on screen. 0 map(s) registered — no view pack applied its HubConfigurations to this hub means the view packs never reached the hub the page renders on; a list of owners means they did, and every one of them declined this control — and the skins and the control's assembly are printed, so a skin no pack knows, or a same-named type loaded from a second assembly, reads off the line directly.

A page with fifty controls of one kind logs one line, not fifty; a different kind on the same hub logs again. Nothing changes on screen.

See UI Extensibility for how to read the line.