Clean up non-editor config in VSCode editor config files (frontend-specific)

Created by: umpox

Description

We have quite a lot of configuration that is either out-of-date or should be tied to config files for a specific tool so it doesn't depend on developers running VSCode for an optimum developer experience.

Sourcegraph search for config files

We should go through our configuration and:

1. Move any necessary config from these files to the relevant tool config. E.g. settings.json -> jest.config.js
2. Remove any unused config, that we don't depend on anymore. E.g. eslint.validate should already be covered by our eslint config.
3. Update any required config that has become out of date (e.g. some commands in task.json do not reference newer projects in the codebase)