feat(vocab): integrate fallback core patterns and enhance vocabulary display in VocabLessonView

- Added a new method in VocabService to merge core pattern glosses with fallback patterns, improving vocabulary clarity and consistency.
- Updated VocabLessonView to utilize the merged core patterns, ensuring a comprehensive vocabulary overview for users.
- Refactored vocabulary handling logic to enhance user experience during vocabulary lessons, including improved display of lesson vocabulary.

backend/scripts/bisaya-course-phase1.js

@@ -0,0 +1,24 @@
+export const BISAYA_PHASE1_DIDACTICS = {
+  'Begrüßungen & Höflichkeit': {
+    corePatterns: [
+      { target: 'Kumusta ka?', gloss: 'Wie geht es dir?' },
+      { target: 'Maayong buntag.', gloss: 'Guten Morgen.' },
+      { target: 'Maayong adlaw.', gloss: 'Guten Tag.' },
+      { target: 'Maayong gabii.', gloss: 'Guten Abend.' },
+      { target: 'Maayong gabii, matulog na ta.', gloss: 'Guten Abend, wir legen uns schlafen.' },
+      { target: 'Katulog og maayo.', gloss: 'Schlaf gut.' },
+      { target: 'Kapoy na ka?', gloss: 'Bist du müde?' },
+      { target: 'Matulog na ta.', gloss: 'Lass uns schlafen gehen.' },
+      { target: 'Inom sa og tubig.', gloss: 'Trink Wasser.' },
+      { target: 'Patya ang suga.', gloss: 'Mach das Licht aus.' },
+      { target: 'Tabuni ang imong kaugalingon.', gloss: 'Deck dich zu.' },
+      { target: 'Ugma nasad.', gloss: 'Bis morgen wieder.' },
+      { target: 'Damgo og nindot.', gloss: 'Träum schön.' },
+      { target: 'Amping.', gloss: 'Pass auf dich auf.' },
+      { target: 'Babay.', gloss: 'Tschüss.' },
+      { target: 'Maayo ko.', gloss: 'Mir geht es gut.' },
+      { target: 'Salamat.', gloss: 'Danke.' },
+      { target: 'Palihug.', gloss: 'Bitte.' }
+    ]
+  }
+};

backend/services/vocabService.js

@@ -12,6 +12,7 @@ import UserParam from '../models/community/user_param.js';
 import { sequelize } from '../utils/sequelize.js';
 import { notifyUser } from '../utils/socket.js';
 import { Op } from 'sequelize';
+import { BISAYA_PHASE1_DIDACTICS } from '../scripts/bisaya-course-phase1.js';
 
 export default class VocabService {
   async _getUserByHashedId(hashedUserId) {
@@ -347,6 +348,27 @@ export default class VocabService {
       });
   }
 
+  _mergeCorePatternGlosses(primaryPatterns = [], fallbackPatterns = []) {
+    const fallbackByTarget = new Map(
+      fallbackPatterns
+        .map((entry) => this._normalizeCorePatternEntry(entry))
+        .filter(Boolean)
+        .map((entry) => [this._normalizeLexeme(entry.target), entry.gloss || ''])
+    );
+
+    return primaryPatterns.map((entry) => {
+      const normalized = this._normalizeCorePatternEntry(entry);
+      if (!normalized) {
+        return null;
+      }
+      if (normalized.gloss) {
+        return normalized;
+      }
+      const gloss = fallbackByTarget.get(this._normalizeLexeme(normalized.target)) || '';
+      return gloss ? { ...normalized, gloss } : normalized;
+    }).filter(Boolean);
+  }
+
   _normalizeStructuredList(value, keys = ['title', 'text']) {
     if (!value) return [];
     if (Array.isArray(value)) {
@@ -560,9 +582,13 @@ export default class VocabService {
 
     const learningGoals = this._normalizeStringList(plainLesson.learningGoals);
     const extractedTrainerVocabs = this._extractTrainerVocabsFromExercises(grammarExercises);
-    const corePatterns = this._enrichCorePatternsWithGloss(
-      this._normalizeCorePatternList(plainLesson.corePatterns),
-      extractedTrainerVocabs
+    const phase1FallbackCorePatterns = BISAYA_PHASE1_DIDACTICS[plainLesson.title]?.corePatterns || [];
+    const corePatterns = this._mergeCorePatternGlosses(
+      this._enrichCorePatternsWithGloss(
+        this._normalizeCorePatternList(plainLesson.corePatterns),
+        extractedTrainerVocabs
+      ),
+      phase1FallbackCorePatterns
     );
     const grammarFocus = this._normalizeStructuredList(plainLesson.grammarFocus, ['title', 'text', 'example']);
     const explicitSpeakingPrompts = this._normalizeStructuredList(plainLesson.speakingPrompts, ['title', 'prompt', 'cue']);
@@ -578,9 +604,12 @@ export default class VocabService {
           ],
       corePatterns: corePatterns.length > 0
         ? corePatterns
-        : this._enrichCorePatternsWithGloss(
-            uniquePatterns.slice(0, 5).map((s) => ({ target: String(s || '').trim(), gloss: '' })).filter((p) => p.target),
-            extractedTrainerVocabs
+        : this._mergeCorePatternGlosses(
+            this._enrichCorePatternsWithGloss(
+              uniquePatterns.slice(0, 5).map((s) => ({ target: String(s || '').trim(), gloss: '' })).filter((p) => p.target),
+              extractedTrainerVocabs
+            ),
+            phase1FallbackCorePatterns
           ),
       grammarFocus: grammarFocus.length > 0 ? grammarFocus : uniqueGrammarExplanations.slice(0, 4),
       speakingPrompts: explicitSpeakingPrompts.length > 0 ? explicitSpeakingPrompts : speakingPrompts.slice(0, 4),