Add a planning agent

Problem/Motivation

The problem right now is that the assistant is not great at knowning what is possible and not possible fromt the agents, because it is missing the context of knowning what exists on the website.

A typical example is if it for instance if the user asks to generate a content type that already exists, the assistant will say that it can do this and show how its planning to do this. And then when its asked to do it, it will fail and tell the user.

Proposed resolution

Add a planning agent that has the context needed to answer if something is possible from the assistant.
The planning agent can lookup data to check the possibility to do different things.
The planning agent will not be able to modify anything.