[Translation][ES] Claim: Spanish translation for missing levels (30-40)

[JulianColoma]

Hi! I would like to contribute by translating the missing levels into Spanish (from level 30 to 40).

Since the Spanish language is already supported, I will focus on:

1. Translating level descriptions under client/src/gamedata/es/descriptions/levels/.
2. Checking if any new keys need to be added to es/strings.json.

I'll be submitting PRs in small batches to facilitate the review. Thanks!