fix(desktop): reopen the splash on activate and keep sign-in returns out of it

Closing the connecting splash during a stalled local boot left Dock activation
doing nothing until the next readiness timeout; activate now reopens it while
waiting for the local backend. Provider sign-in returns now load only into the
main window, never the splash, where they would be lost on dismissal.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
07ca044999Julius Marminge committed on 10/22/2026, 1:25:37 PMparent940d828
4 files changedLine totals unavailable