[Feature request] Add ability to configure js_render only on specific URLs

[bogdbo]

Description

Hello typesense team,

I've discussed this on slack with @tharropoulos and I'm raising a feature request for you to assess how useful this would be to the wider community.

Steps to reproduce

setting js_render=true will evaluate every single page with selenium. There are scenarios where only a handful of pages need to be evaluated with js_render=true (for instance docusaurus with redocusaurus plugin, only redoc pages need js_render=true).

Expected behaviour

Have the ability to define js_render=true per start_url blocks or any other way that makes sense, suggested eg:

 "start_urls": [
    {
      "url": "http://some-url/tools",
      "js_render": true
    },
    {
      "url": "http://some-url/overview"
    }
 ]