IDE, wizards: update Kotlin/JS support in jvm server / js client

Configure js browser sub target to use new test and application runners.
Rework js linking and packaging:
- get rid of required.js
- use builtin jsBrowserWebpack task, embed js bundle into jvm jar, remove gradle boilerplate
- ktor server: serve js bundle resource, remove boilerplate

#KT-31695 Fixed
#KT-31099 Fixed

Author: snrostov