bugfixing; fixed toolbox; isolated [Base|AI|Human]Message crap logic to the agent interface; implemented tests

implemented graph.py, agents, guard; reduced image and video node to viewer node; renamed system prompts

embracing langgraph; addapted LLMFactory, Args.LLMInterface, IAgent, Toolbox and agents.py; simplified graph: removed math and encryption agents while promoting the reasoner

New approach: langgraph only