Automate unused files, dependencies and exports removal of dead code

[cnotv]

Description

Automate removal of dead code within the project, which has been witnessed to happen often in our codebase due to its size.

Context

There are different options to achieve this:

• CI dry run with warnings
• Integration with husky/lint-staged https://github.com/rancher/dashboard/issues/9634 (leverage GH workload)
• Single command integration

Candidate tool: https://github.com/webpro-nl/knip

[cnotv]

We can definitely postpone this one as it's not a blocker for the migration anymore.