Express migration (#80)

* Initial migration

* Cleanup and create migration scripts

* Introduce test suite

* Fix test issues

* Correct CORS issue and update paths

* Update README

backend/tests/helpers/setup.js

@@ -0,0 +1,39 @@
+// Set test environment before importing models
+process.env.NODE_ENV = 'test';
+
+const { sequelize } = require('../../models');
+
+beforeAll(async () => {
+  await sequelize.sync({ force: true });
+}, 30000);
+
+beforeEach(async () => {
+  // Clean all tables except Sessions to avoid conflicts
+  try {
+    const models = Object.values(sequelize.models);
+    const nonSessionModels = models.filter(model => model.name !== 'Session');
+    await Promise.all(nonSessionModels.map(model => model.destroy({ truncate: true, cascade: true })));
+  } catch (error) {
+    // Ignore errors during cleanup
+  }
+});
+
+afterEach(async () => {
+  // Clean up sessions after each test
+  try {
+    const Session = sequelize.models.Session;
+    if (Session) {
+      await Session.destroy({ truncate: true });
+    }
+  } catch (error) {
+    // Ignore errors during session cleanup
+  }
+});
+
+afterAll(async () => {
+  try {
+    await sequelize.close();
+  } catch (error) {
+    // Database may already be closed
+  }
+}, 30000);