docs: add Spanish README translation

[InlitX]

Hi there! 👋 I've added a complete manual translation of the

README.md into Spanish (README.es.md)
to help make this awesome project more accessible to the Hispanic community.

[CLAassistant]

All committers have signed the CLA.

[wj-xiao]

AI-assisted review found two blocking documentation issues in README.es.md:

1. Large parts of the middle/later sections appear to be garbled machine translation and are not reliably readable in Spanish.
2. The troubleshooting and web-search sections contain corrupted explanations and examples that may mislead users.

Could you please re-check the Spanish content carefully and confirm that the translation is accurate and readable end to end? At the moment, the AI-assisted review does not consider this version safe to merge without another manual pass.

[InlitX]

Hi! Thanks for catching that. I rewrote the entire translation from scratch — I had used DeepL initially to speed things up, but it introduced quite a few errors so I redid it manually this time and reviewed it carefully throughout. Should be solid now, but let me know if anything still looks off!

[yinwm]

@InlitX plz resolve conflicts

[InlitX]

@yinwm Done, conflicts resolved!