Add logging for model synchronization and cache handling in syncDatabase.js

Enhance sequelize.js by adding a console log to indicate when models are being synced without constraints. Update syncDatabase.js to include important notes on caching issues with Node.js ES-Modules and log the model loading process during deployment synchronization.

backend/utils/sequelize.js

@@ -478,6 +478,7 @@ const syncModelsAlways = async (models) => {
             try {
                 // constraints: false verhindert, dass Sequelize Foreign Keys automatisch erstellt
                 // Foreign Keys sollten nur über Migrations verwaltet werden
+                console.log(`  🔄 Syncing model ${model.name} with constraints: false`);
                 await model.sync({ alter: true, force: false, constraints: false });
             } finally {
                 // Restore VIRTUAL fields after sync