#55: Add SuccessToast after new resource is created. ResourceModal gains an
optional onSuccess(displayName) prop; ResourcesClient wires it to a toast
that auto-dismisses after 2.5 s.
#56: Fix useFocusTrap stale-closure bug. Focusable elements are now queried
dynamically inside handleKeyDown (not captured once at mount), so Tab
navigation stays correct as the form re-renders. Initial focus is deferred
via requestAnimationFrame so the browser layout is stable before focus() fires.
Co-Authored-By: claude-flow <ruv@ruv.net>