feat(app): show and write a word's senses with their grammar

A word with senses (as a dictionary gives them) shows them when its
answer shows: numbered when there are several, each with its label, its
translations and its grammar codes, small and slanted, their meaning on
hover. A word usually written in kana shows its reading from the start:
its kanji are rarely seen, so there is nothing to hide. The composer
writes the senses' translations, adds and removes senses, and keeps the
codes as they came.

The codes' short forms and meanings are the dictionary's own English
(JMdict's entities), kept as data beside the cards.

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/lib/l10n/app_localizations_en.dart

@@ -1567,6 +1567,21 @@ class AppLocalizationsEn extends AppLocalizations {
   @override
   String get vocabularyRemoveMeaning => 'Remove meaning';
 
+  @override
+  String get vocabularyGlossHint => 'Translation';
+
+  @override
+  String get vocabularyAddGloss => 'Add translation';
+
+  @override
+  String get vocabularyRemoveGloss => 'Remove translation';
+
+  @override
+  String get vocabularyAddSense => 'Add sense';
+
+  @override
+  String get vocabularyRemoveSense => 'Remove sense';
+
   @override
   String get matchingCategories => 'Categories';