Fix ESM bundle missing named exports

esbuild.js

@@ -79,6 +79,7 @@ async function run() {
 
     options.outfile = `${outdir}/mqtt.esm.js`
     options.format = 'esm'
+    options.entryPoints = ['build/index.esm.js']
 
     await build(options)
 

src/index.esm.ts

@@ -0,0 +1,20 @@
+// ESM entry point for browser bundle
+// This file explicitly re-exports using ES6 syntax to ensure
+// esbuild properly creates named exports in the ESM bundle
+
+import * as mqtt from './mqtt'
+
+export default mqtt
+export {
+	connect,
+	connectAsync,
+	MqttClient,
+	Client,
+	Store,
+	DefaultMessageIdProvider,
+	UniqueMessageIdProvider,
+	KeepaliveManager,
+} from './mqtt'
+
+// Re-export all other exports
+export * from './mqtt'

src/index.ts

@@ -2,3 +2,15 @@ import * as mqtt from './mqtt'
 
 export default mqtt
 export * from './mqtt'
+
+// Explicit re-exports for ESM bundle compatibility
+export {
+	connect,
+	connectAsync,
+	MqttClient,
+	Client,
+	Store,
+	DefaultMessageIdProvider,
+	UniqueMessageIdProvider,
+	KeepaliveManager,
+} from './mqtt'