Spanish translation doesn't work

[diegorodriguezv]

I'm getting a Not Found error at: https://doc.rust-lang.org/stable/rust-by-example/es/index.html
The japanese and chinese versions work okay.
I tried building it locally and it seems to work.

[marktech0813]

Hi, Can I handle this issues now?

[marktech0813]

I just fixed issues. Please check PR.

[marktech0813]

Please check PR, I added a runtime check in the language picker so unavailable locales are hidden, preventing 404s like the Spanish URL on doc.rust-lang.org. This keeps working languages (ja/zh) visible and avoids broken links when a locale isn’t deployed.