Add language assistant settings and related features: Introduce new routes and controller methods for managing language assistant settings, including retrieval and saving of LLM configurations. Update navigation structure to include language assistant options. Enhance vocab course model to support additional learning attributes such as learning goals and core patterns. Update SQL scripts to reflect new database schema changes for vocab courses. Improve localization for language assistant settings in German and English.

backend/sql/add_language_assistant_user_params.sql

@@ -0,0 +1,24 @@
+-- Sprachassistent / LLM: Einstellungen über type.settings + type.user_param + community.user_param
+-- (keine Spalten mehr an community.user).
+--
+-- Falls du vorher add_user_llm_columns.sql ausgeführt hast: Spalten an user wieder entfernen.
+ALTER TABLE community."user" DROP COLUMN IF EXISTS llm_api_key_encrypted;
+ALTER TABLE community."user" DROP COLUMN IF EXISTS llm_settings;
+
+-- Gruppe „languageAssistant“
+INSERT INTO type.settings (name)
+SELECT 'languageAssistant'
+WHERE NOT EXISTS (SELECT 1 FROM type.settings WHERE name = 'languageAssistant');
+
+-- Param-Typen (description eindeutig)
+INSERT INTO type.user_param (description, datatype, settings_id, order_id, immutable, min_age, gender, unit)
+SELECT 'llm_settings', 'string', s.id, 900, false, NULL, NULL, NULL
+FROM type.settings s
+WHERE s.name = 'languageAssistant'
+  AND NOT EXISTS (SELECT 1 FROM type.user_param p WHERE p.description = 'llm_settings');
+
+INSERT INTO type.user_param (description, datatype, settings_id, order_id, immutable, min_age, gender, unit)
+SELECT 'llm_api_key', 'string', s.id, 901, false, NULL, NULL, NULL
+FROM type.settings s
+WHERE s.name = 'languageAssistant'
+  AND NOT EXISTS (SELECT 1 FROM type.user_param p WHERE p.description = 'llm_api_key');