MPP/JS code completion in HTML editor

I have a full-stack Kotlin MPP with three modules (‘client’, ‘server’ and ‘shared’).
The client project contains static HTML pages which reference the generated js code with

<script type="text/javascript" src="./client.js"></script>

However, the Intellij HMTL editor will mark ./client.js as cannot resolve file 'client.js' and code in <script> tags does not provide js code completion or link to the Kotlin source code.

How do I get js code completion in the HTML editor for code that is in the same project?