Add global event pipeline.

Add message editor back.

src/lib/eventEmitter.ts

@@ -0,0 +1,18 @@
+import EventEmitter from "eventemitter3";
+export const InternalEvent = new EventEmitter();
+
+export function internalSubscribe(ns: string, event: string, fn: (...args: any[]) => void) {
+    InternalEvent.addListener(ns + '/' + event, fn);
+    return () => InternalEvent.removeListener(ns + '/' + event, fn);
+}
+
+export function internalEmit(ns: string, event: string, ...args: any[]) {
+    InternalEvent.emit(ns + '/' + event, ...args);
+}
+
+// Event structure: namespace/event
+
+/// Event List
+// - MessageRenderer/edit_last
+// - MessageRenderer/edit_message
+// - MessageBox/focus