Update MongoDB connection settings and enhance debugging capabilities

backend/config/database.js

@@ -1,6 +1,11 @@
 module.exports = async function (mongoose) {
     try {
-        await mongoose.connect(process.env.CONNECTION_URI);
+        console.log('🔌 Attempting to connect with URI:', process.env.CONNECTION_URI);
+        await mongoose.connect(process.env.CONNECTION_URI, {
+            useNewUrlParser: true,
+            useUnifiedTopology: true,
+            directConnection: true,
+        });
         console.log('✅ MongoDB connected');
     } catch (err) {
         console.error('❌ MongoDB connection error:', err);

backend/config/session.js

@@ -1,10 +1,41 @@
 const session = require('express-session');
 const MongoDBStore = require('connect-mongodb-session')(session);
 
-const store = new MongoDBStore({
-    uri: process.env.CONNECTION_URI,
+console.log('📋 Session.js - CONNECTION_URI:', process.env.CONNECTION_URI);
+
+// Parse the connection URI to extract connection options
+const uriString = process.env.CONNECTION_URI;
+const uriUrl = new URL(uriString);
+
+// Extract individual components
+const baseUri = `${uriUrl.protocol}//${uriUrl.username}:${uriUrl.password}@${uriUrl.hostname}:${uriUrl.port}${uriUrl.pathname}`;
+const replicaSet = uriUrl.searchParams.get('replicaSet');
+const authSource = uriUrl.searchParams.get('authSource');
+
+console.log('📋 Base URI:', baseUri);
+console.log('📋 ReplicaSet:', replicaSet);
+console.log('📋 AuthSource:', authSource);
+
+// Build connection options with directConnection to bypass replica set discovery
+const connectionOptions = {
+    useNewUrlParser: true,
+    useUnifiedTopology: true,
+    directConnection: true, // Force direct connection to specified server
+};
+
+if (authSource) {
+    connectionOptions.authSource = authSource;
+}
+
+const storeOptions = {
+    uri: baseUri,
     collection: 'sessions',
-});
+    connectionOptions: connectionOptions,
+};
+
+console.log('📋 Store options:', JSON.stringify(storeOptions, null, 2));
+
+const store = new MongoDBStore(storeOptions);
 const sessionMiddleware = session({
     store: store,
     credentials: true,