Manage DNS records for a domain on DigitalOcean via API (A, CNAME, MX, TXT, apex records)

Documented steps

1. Add the domain to DigitalOcean DNS first (POST https://api.digitalocean.com/v2/domains with {"name":"example.com"}) and point the registrar's nameservers at ns1/ns2/ns3.digitalocean.com.
2. Create records with POST https://api.digitalocean.com/v2/domains/{domain_name}/records. Official example: curl -X POST -H 'Content-Type: application/json' -H 'Authorization: Bearer $DIGITALOCEAN_TOKEN' -d '{"type":"A","name":"www","data":"162.10.66.0","priority":null,"port":null,"ttl":1800,"weight":null,"flags":null,"tag":null}' https://api.digitalocean.com/v2/domains/example.com/records
3. Field shapes: A/AAAA -> name = hostname ('www' or '@'), data = IP. CNAME -> name = subdomain, data = target hostname. MX -> name usually '@', data = mail server hostname, priority = positive integer (required). TXT -> name = hostname, data = text value. Use '@' as name to target the apex/root domain.
4. List/inspect records with GET /v2/domains/{domain_name}/records (filterable), update one with PUT /v2/domains/{domain_name}/records/{record_id}, delete with DELETE on the same path.
5. Docs: https://docs.digitalocean.com/products/networking/dns/how-to/manage-records/