feat(bisaya-course): refine phase 4 didactics and enhance course content generation

- Corrected grammatical errors and improved the phrasing in the BISAYA_PHASE4_DIDACTICS, ensuring clarity and accuracy in the learning materials.
- Updated the course content generation script to include lessons from phase 5, enhancing the overall structure and flow of the course.
- Introduced a new vocabulary course content synchronization process, improving the integration of vocabulary resources across different modules.
- Enhanced the VocabService to dynamically adjust temperature settings based on the mode, optimizing response generation for different contexts.
- Added new localized titles and vocabulary entries in multiple languages, enriching the learning experience for users.

backend/services/vocabService.js

@@ -2798,6 +2798,13 @@ export default class VocabService {
     const controller = new AbortController();
     const timeout = setTimeout(() => controller.abort(), 30000);
 
+    const temperatureByMode = {
+      explain: 0.4,
+      practice: 0.5,
+      correct: 0.1
+    };
+    const temperature = Number.isFinite(temperatureByMode[mode]) ? temperatureByMode[mode] : 0.5;
+
     let response;
     try {
       response = await fetch(endpoint, {
@@ -2806,7 +2813,7 @@ export default class VocabService {
         signal: controller.signal,
         body: JSON.stringify({
           model: config.model,
-          temperature: 0.7,
+          temperature,
           messages: [
             {
               role: 'system',