implemented frontend including separate message system; started to implement backend

yjs-poll/node_modules/lib0/performance.node.js

@@ -0,0 +1,21 @@
+import { performance } from 'node:perf_hooks'
+import { nop } from './function.js'
+import * as time from './time.js'
+
+/**
+ * @type {typeof performance.measure}
+ */
+/* c8 ignore next */
+export const measure = performance.measure ? performance.measure.bind(performance) : /** @type {any} */ (nop)
+
+/**
+ * @type {typeof performance.now}
+ */
+/* c8 ignore next */
+export const now = performance.now ? performance.now.bind(performance) : time.getUnixTime
+
+/**
+ * @type {typeof performance.mark}
+ */
+/* c8 ignore next */
+export const mark = performance.mark ? performance.mark.bind(performance) : /** @type {any} */ (nop)