Make Decidim codebase more compatible with agentic-development approach

Is your feature request related to a problem? Please describe.

Agentic-development approach will be a standard in a near future and the results provided depends a lot on the context we provide.

Describe the solution you'd like

A default context describing how to write the code using the standards so we have a better solution from the agents.

Study the current standards used by the current code agents and write the context where the agent can get more details, how the final solution should be, and wich steps should follow.

Describe alternatives you've considered

N/A

Additional context

N/A

Could this issue impact on users private data?