feat(dictionary): characters of Chinese, Korean and Greek, written by hand; pinyin typed

Parity with Japanese's kanji and kana:

- The characters' tab is named by its language (Hanzi, Hangul & Hanja,
  Alphabet), its groups too: HSK levels and the characters in common use
  (Hong Kong's grades for traditional ones); Hangul and the Hanja taught
  in schools; Greek's letters. Radicals for Chinese and Korean in their
  own forms (讠 for 言 in simplified Chinese), none for Greek.
- A character's readings are named as its language names them: On and
  Kun, Pinyin, Eum and Hun (음, 훈); a letter means its sound and name.
- How characters are written comes by language: Chinese from Make Me a
  Hanzi (its medians in KanjiVG's square, Arphic Public License, a data
  file beside the app, never in cards), the Hangul letters drawn by the
  curator; a Korean word is written letter by letter (닭: ㄷ ㅏ ㄺ). Words
  of alphabets (German, Greek) aren't written by hand.
- A Chinese word's pinyin is typed in a session, tone numbers turning
  into marks (ni3 → nǐ); KRDict's levels (초급, 중급, 고급) tag Korean
  words; a Korean word's pronunciation shows in brackets ([가치]).
- Smaller: Look up in the composer keeps a noun's article; the Watch
  filter names its level list; hints and placeholders by language.

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/dictionary/dictionary_screen_test.dart

@@ -72,8 +72,9 @@ void main() {
     await tester.pumpAndSettle();
   }
 
-  /// Opens the studyset [id]: `japanese` (Japanese with English meanings)
-  /// or `german`, on an instance with JMdict ([dictionaries]), at
+  /// Opens the studyset [id]: `japanese` (Japanese with English meanings),
+  /// `german`, `greek` or `chinese`, on an instance with JMdict
+  /// ([dictionaries]), at
   /// [location] (the studyset's screen unless given).
   Future<void> show(
     WidgetTester tester, {
@@ -107,6 +108,28 @@ void main() {
             backLanguage: 'en',
           ),
         ),
+      )
+      ..receiveRemoteChange(
+        'greek',
+        encodeStudysetPayload(
+          StudysetContent(
+            title: 'Greek',
+            description: RichContent.empty(),
+            frontLanguage: 'el',
+            backLanguage: 'en',
+          ),
+        ),
+      )
+      ..receiveRemoteChange(
+        'chinese',
+        encodeStudysetPayload(
+          StudysetContent(
+            title: 'Chinese',
+            description: RichContent.empty(),
+            frontLanguage: 'zh-Hans',
+            backLanguage: 'en',
+          ),
+        ),
       );
     await pumpApp(
       tester,
@@ -259,6 +282,76 @@ void main() {
     expect(made.content.entry, (source: 'kanjidic', id: '食'));
   });
 
+  testWidgets("Greek's letters in a tab of their own, without radicals, "
+      'added whole as character cards', (tester) async {
+    await show(
+      tester,
+      id: 'greek',
+      dictionaries: FakeDictionaryGateway(
+        available: [wiktionaryEl, greekAlphabet],
+        words: [
+          character(
+            'Β β',
+            labels: ['greek'],
+            romaji: 'v',
+            name: 'βήτα (beta)',
+            of: greekAlphabet,
+          ),
+        ],
+      ),
+    );
+    await addMaterial(tester, 'From the dictionary');
+
+    expect(find.text('Radicals'), findsNothing);
+    await tester.tap(find.text('Alphabet'));
+    await settle(tester);
+    expect(find.text('Letters'), findsOneWidget);
+    await tester.tap(find.text('Greek alphabet').hitTestable());
+    await tester.pumpAndSettle();
+    await tester.tap(find.text('Add 1 character'));
+    await tester.pumpAndSettle();
+
+    final made = (await cards.cardsOf('greek')).single;
+    expect(made.content.front.plainText.trim(), 'Β β');
+    expect(made.content.meanings, ['v', 'βήτα (beta)']);
+  });
+
+  testWidgets('Chinese characters by HSK level and in common use, beside '
+      'the radicals in their simplified forms', (tester) async {
+    await show(
+      tester,
+      id: 'chinese',
+      dictionaries: FakeDictionaryGateway(
+        available: [ccCedictHans, unihanHans],
+        words: [
+          character(
+            '说',
+            meanings: ['speak'],
+            on: ['shuō'],
+            labels: ['hsk:1', 'common', 'radical:149'],
+            of: unihanHans,
+          ),
+        ],
+      ),
+    );
+    await addMaterial(tester, 'From the dictionary');
+
+    await tester.tap(find.text('Hanzi'));
+    await settle(tester);
+    expect(find.text('HSK levels'), findsOneWidget);
+    expect(find.text('In common use'), findsOneWidget);
+    expect(find.text('HSK 1'), findsOneWidget);
+    await tester.tap(find.text('Radicals'));
+    await settle(tester);
+    // 言 as simplified Chinese writes it at a character's side.
+    await tester.scrollUntilVisible(
+      find.text('讠'),
+      400,
+      scrollable: find.byType(Scrollable).last,
+    );
+    expect(find.text('讠'), findsOneWidget);
+  });
+
   testWidgets('a character found shows its readings and strokes, and is '
       'added as a card', (tester) async {
     await show(tester, dictionaries: withKanji());