feat: add onTTI declaration

Author: Inchill

CHANGELOG.md

@@ -1,4 +1,4 @@
-# 1.0.0 (2023-09-25)
+# 0.0.4 (2023-09-25)
 
 
 ### Features

README.md

@@ -10,18 +10,24 @@ Easily measure performance metrics of time to interactive in JavaScript.
 npm i @inchill/time-to-interactive
 ```
 
+Or
+
+```shell
+yarn add @inchill/time-to-interactive
+```
+
 ```js
 import { onTTI } from '@inchill/time-to-interactive';
 
 onTTI(res => console.log(res));
 ```
 
+
+
 ## Browser Support
 
 The `time-to-interactive` code will run without error in all major browsers as well as Internet Explorer back to version 11. So, `onTTI` is currently only available in Chromium-based browsers (e.g. Chrome, Edge, Opera, Samsung Internet).
 
-## Development
-
 ## License
 
 [MIT](/LICENSE)

types/index.d.ts

@@ -43,3 +43,11 @@ export interface TTIMetric extends Metric {
 export interface TTIReportCallback {
   (metric: Metric): void;
 }
+
+/**
+ * Calculates the [TTI](https://web.dev/tti/) value for the current page and
+ * calls the `callback` function once the value is ready, along with the
+ * relevant `paint` performance entry used to determine the value. The reported
+ * value is a `DOMHighResTimeStamp`.
+ */
+export declare const onTTI: (onReport: TTIReportCallback) => void;