Enhance exercise generation for family conversations and feelings & affection

- Updated multiple choice exercises to include randomized wrong options for improved engagement and challenge.
- Added new exercise types for reading aloud and speaking from memory, enhancing interactive learning experiences.
- Improved gap fill exercises with clearer instructions and multiple variants for better user understanding.
- Enhanced the vocabulary service to support new exercise types, ensuring robust answer checking and feedback mechanisms.
- Updated localization files to include new instructions and messages related to the new exercise types.

backend/sql/add-speaking-exercise-types.sql

@@ -0,0 +1,16 @@
+-- ============================================
+-- Neue Übungstypen für Sprachproduktion hinzufügen
+-- ============================================
+-- Führe diese Queries direkt auf dem Server aus
+
+-- Neue Übungstypen hinzufügen
+INSERT INTO community.vocab_grammar_exercise_type (name, description) VALUES
+    ('reading_aloud', 'Laut vorlesen - Übung zur Verbesserung der Aussprache'),
+    ('speaking_from_memory', 'Aus dem Kopf sprechen - Übung zur aktiven Sprachproduktion')
+ON CONFLICT (name) DO NOTHING;
+
+-- ============================================
+-- Hinweis:
+-- - reading_aloud: Text wird angezeigt, User liest vor, Speech Recognition prüft
+-- - speaking_from_memory: Prompt wird angezeigt, User spricht frei, manuelle/automatische Bewertung
+-- ============================================