add tests

Author: sayhiben

.claude/settings.local.json

@@ -0,0 +1,11 @@
+{
+  "permissions": {
+    "allow": [
+      "Bash(npm install:*)",
+      "Bash(npm test:*)",
+      "Bash(npm run test:coverage:*)",
+      "Bash(node:*)"
+    ],
+    "deny": []
+  }
+}

jest.config.js

@@ -0,0 +1,33 @@
+module.exports = {
+  testEnvironment: 'node',
+  coverageDirectory: 'coverage',
+  collectCoverageFrom: [
+    '**/*.js',
+    '!coverage/**',
+    '!jest.config.js',
+    '!**/node_modules/**',
+    '!migrations/**',
+    '!config/**',
+    '!tests/**',
+    '!**/*.test.js',
+    '!**/*.spec.js',
+    '!bin/www'
+  ],
+  testMatch: [
+    '**/tests/**/*.test.js',
+    '**/?(*.)+(spec|test).js'
+  ],
+  testPathIgnorePatterns: [
+    '/node_modules/'
+  ],
+  coverageThreshold: {
+    global: {
+      branches: 95,
+      functions: 95,
+      lines: 99,
+      statements: 99
+    }
+  },
+  setupFilesAfterEnv: ['<rootDir>/tests/setup.js'],
+  testTimeout: 10000
+};