fix(test): eliminate Winston uncaughtException listener leak

jest.config.js

@@ -162,6 +162,10 @@ export default {
   // The test environment that will be used for testing
   testEnvironment: 'node',
 
+  // Force Jest to exit after all tests complete — prevents hanging on open MongoDB
+  // handles from integration tests whose afterAll disconnect races with Jest's exit
+  forceExit: true,
+
   // Global timeout for tests and hooks (integration tests bootstrap MongoDB + Express)
   testTimeout: 15000,
 

lib/services/logger.js

@@ -28,7 +28,11 @@ const logger = new winston.createLogger({
     new winston.transports.Console({
       level: logLevel,
       format: consoleFormat,
-      handleExceptions: true,
+      // Disable exception handling in test env — each jest.resetModules() re-imports
+      // this module, and handleExceptions:true registers a new process.uncaughtException
+      // listener on every import without ever removing the old one, causing listener
+      // accumulation and heap growth across module reloads in beforeEach hooks.
+      handleExceptions: process.env.NODE_ENV !== 'test',
     }),
   ],
   exitOnError: false,
@@ -71,7 +75,8 @@ const getLogOptions = () => {
     eol: '\n',
     tailable: true,
     showLevel: true,
-    handleExceptions: true,
+    // Same guard as the Console transport — see comment at top of createLogger call
+    handleExceptions: process.env.NODE_ENV !== 'test',
     humanReadableUnhandledException: true,
   };
 };