Document the validator

[torives]

📚 Context

The node repository has several Markdown files detailing the node's capabilities and how it works. This documentation has to be updated to reflect the changes introduced by the new validator component

✔️ Solution

Edit the documentation files, removing the references to the server-manager the validator is replacing and adding information about its role in the system, data flow, and interactions with other components

📈 Subtasks

• Edit README.md
• Edit architecture.md