docs: add jsdocs badge

Author: userquin

README.md

@@ -2,6 +2,7 @@
 
 [![npm version][npm-version-src]][npm-version-href]
 [![npm downloads][npm-downloads-src]][npm-downloads-href]
+[![JSDocs][jsdocs-src]][jsdocs-href]
 [![License][license-src]][license-href]
 [![Nuxt][nuxt-src]][nuxt-href]