fix: one choice per run, taps seen before acting

Answers code_audit_20 and tui_audit_13. A tap acts on the frame it was
made on, bar entries that install, quit or open Confirm take two taps,
and Preferred regions keep their rows while open. Every check of a list
keeps the systems ticked, the plan's counts read the list the check
read, line mode leaves game data out of the choice alone, Confirm counts
copies, a pack's missing files are said before a size, and paths break
after a separator only.

tests/test_install_experience.py

@@ -1241,7 +1241,7 @@ class OfflineWithNothingFound(unittest.TestCase):
         said = proc.stdout + proc.stderr
         self.assertEqual(proc.returncode, 1, said)
         self.assertNotIn("emudeck", said.lower())
-        self.assertIn("Use --platform and --dest", said)
+        self.assertIn("Name the setup with --platform and its folder with --dest", said)
 
 
 class TheDryRunWords(unittest.TestCase):