test(app): tap the multiple-choice option, not its text

The option's text sits in an IgnorePointer, so the read-only editor
drawing it doesn't take taps for selecting text. Tapping the text made
tap() warn that its centre doesn't hit it; the InkWell around it took
the tap anyway. Tap the option's InkWell instead.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Signed-off-by: Tizian 「ティツィアーン」 <raisondetredev@pm.me>

halkyon_learn_flutter/test/feature/study/widget/study_screen_test.dart

@@ -142,7 +142,13 @@ void main() {
     Finder check() => find.widgetWithText(FilledButton, 'Check');
     expect(tester.widget<FilledButton>(check()).onPressed, isNull);
 
-    await tester.tap(find.textContaining('Kyoto', findRichText: true));
+    // The option takes the tap: its text ignores pointers.
+    await tester.tap(
+      find.ancestor(
+        of: find.textContaining('Kyoto', findRichText: true),
+        matching: find.byType(InkWell),
+      ),
+    );
     await tester.pump();
     await tester.tap(check());
     await tester.pumpAndSettle();