Move IDE routes from VUE to Rails

What does this MR do?

In this MR we move the routing initialization responsibility from the Vue router to Rails. This way we can provide information to the IDE beforehand when it loads, avoiding some extra calls.

This routing does not replace the Vue routing, but rather supplements it. WebIDE is still a Vue-based SPA, but we need all the information to set up the app upfront.

Does this MR meet the acceptance criteria?

Conformity

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