Spanish, fourth of Phase 1

781 of 796 strings; the fifteen left are product names, bare URLs and example
addresses. Generated by AI, unreviewed, marked Beta.

Register is "usted", following the other three. Spanish makes the decision
cheaper than they did: most of an interface is infinitives and nouns --
"Eliminar", "Configuración" -- where the question never arises. It only shows
in the sentences that address the reader directly, and those agree.

This is peninsular Spanish where the varieties diverge, chosen deliberately
rather than blended, because a blend reads worse than either. The file names
the differences that actually matter in a mail client -- "correo" over
"email", "ordenador" over "computadora" -- and notes that a Latin American
catalogue would be a copy of this one with those changed, not a fresh
translation. Worth writing down while the reasoning is fresh rather than
rediscovering it if es-419 is ever asked for.

"Etiqueta" for label, as in French: Gmail established it and a reader will
find it there. That is the third application of the same rule -- use what the
reader will meet elsewhere -- and the third different outcome, which is what
a rule looks like when it is doing work.

web/src/lib/languages.ts

@@ -38,6 +38,7 @@ export interface UiLanguage {
 export const UI_LANGUAGES: readonly UiLanguage[] = [
   { tag: "en", name: "English" },
   { tag: "de", name: "Deutsch", beta: true },
+  { tag: "es", name: "Español", beta: true },
 ];
 
 /** Where to report a bad translation. Beta languages depend on it. */