Add a public DNS resolver from an unrepresented region (Africa / South America / Middle East / Oceania)

Our resolver list currently covers US, CH, CA, CY, CN and the EU. Whole continents are missing. If you know a well-known public resolver operated from an unrepresented region, add it:

• One object in api/data/dns-resolvers.js — the header comment has the entry shape and rules (UDP IPv4 and/or JSON-API DoH; country = operator's home, uppercase ISO alpha-2).
• Please pick services that are publicly documented and intended for public use, not a random open resolver.
• The list is curated, not exhaustive — every entry adds one upstream query per lookup, so one solid resolver per region beats five obscure ones.

pnpm check green. Comment to claim (mention which resolver you're adding); PR targets dev.