Remember the TUI server selection

TESTING.md

@@ -75,6 +75,10 @@ representative repositories.
 - [ ] Server profiles can be added, authenticated, selected, edited, renamed,
       and deleted. Blank token on edit preserves the existing token; removing
       the last server leaves the server manager available.
+- [ ] Select a different server, quit, and relaunch without `--server`; the TUI
+      restores that server. Relaunch with `--server NAME`; the explicit server
+      wins and becomes the restored server after a clean exit. Renaming or
+      deleting the remembered profile leaves a valid selection.
 - [ ] Editors move between fields with Tab/Shift-Tab, support cursor movement,
       Unicode insertion, Delete, and Backspace without navigating back, mask
       tokens, save with Ctrl-S, and cancel with Esc.