Read only kue web app

I have made the web app read-only for our forked version of kue. This is the [commit](https://github.com/newscred/kue/commit/f520d739f404451e0c2fcb51bba9e81d6af267dd).

@behrad Can you please help me how to make this configurable by passing an optional argument during kue instantiation, so that I can open a PR to main kue repo?

Start by inspecting the linked commit and the kue web app entry point, then trace how kue is instantiated. Determine where an optional read-only setting can be passed and verify that the web app respects it while existing behavior remains unchanged.

Written by the indexing model from the issue text.