Function add_aaaa_record 

pub async fn add_aaaa_record(
    zone_name: &str,
    name: &str,
    ipv6_addresses: &[String],
    ttl: Option<i32>,
    server: &str,
    key_data: &RndcKeyData,
) -> Result<()>

Add AAAA records using dynamic DNS update (RFC 2136) with RRset synchronization.

This function implements declarative RRset management:

1. Compares existing DNS records with desired IPv6 addresses
2. If mismatch, deletes entire RRset and recreates with desired IPs
3. If match, skips update (idempotent)

Arguments

• zone_name - DNS zone name (e.g., “example.com”)
• name - Record name (e.g., “www” for www.example.com, or “@” for apex)
• ipv6_addresses - List of IPv6 addresses for round-robin DNS
• ttl - Time to live in seconds (None = use zone default)
• server - DNS server address with port (e.g., “10.0.0.1:53”)
• key_data - TSIG key for authentication

Errors

Returns an error if the DNS update fails or the server rejects it.