feat(mini): add compact native EasyTier client (#2479)

Add a native EasyTier proof-of-concept binary with TCP and UDP
transports, TUN, UDP hole punching, AES-GCM, and a read-only RPC
portal.

Introduce a release-derived mini profile and musl linker policy so
x86_64, big-endian MIPS, and little-endian MIPS stay below the strict
5,000,000-byte target without UPX.

easytier/src/instance/dns_server/server_instance.rs

@@ -403,7 +403,7 @@ impl MagicDnsServerInstance {
         rpc_server.set_hook(data.clone());
 
         // Use configured tld_dns_zone or fall back to DEFAULT_ET_DNS_ZONE if empty
-        let flags = global_ctx.config.get_flags();
+        let flags = global_ctx.get_flags();
         let tld_dns_zone_clone = flags.tld_dns_zone.clone();
 
         data.update_dns_records(std::iter::empty(), &tld_dns_zone_clone)