feat(library): Import and Refresh behind one menu button

The library's top bar had a button each for Import and Refresh. Pulling
the list down refreshes too, and is the quicker way on a phone, so both
now sit in a menu ("Library options"), leaving the bar to Search.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01MMm7usAo6q9ZZRoPkWjoxi
Signed-off-by: Tizian 「ティツィアーン」 <raisondetredev@pm.me>

halkyon_learn_flutter/test/feature/archive/import_archive_test.dart

@@ -44,7 +44,9 @@ void main() {
   }
 
   Future<void> choose(WidgetTester tester) async {
-    await tester.tap(find.byTooltip('Import'));
+    await tester.tap(find.byTooltip('Library options'));
+    await tester.pumpAndSettle();
+    await tester.tap(find.text('Import'));
     await tester.pumpAndSettle();
     await tester.tap(find.text('Halkyon archive'));
     await tester.pump();