chore: 添加 EventBus

* 並讓對話列表先用上了

client/EventBus.ts

@@ -0,0 +1,12 @@
+export default class EventBus {
+    static events: { [key: string]: () => void } = {}
+    static on(eventName: string, func: () => void) {
+        this.events[eventName] = func
+    }
+    static off(eventName: string) {
+        delete this.events[eventName]
+    }
+    static emit(eventName: string) {
+        this.events[eventName]()
+    }
+}