[WIP] Extend Agents entity to retrieve stats and skills values

[Copilot]

Thanks for asking me to work on this. I will get started on it and keep this PR's description up to date as I form a plan and make progress.

Original prompt

Extend the Agents entity to retrieve values of stats and skills.
It should support:

• all values of a level.
  Instead of the level, you can specify a stat name or skill name to get only that value.

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