SuiNS: Resolve names

Purpose

SuiNS is Sui's name service — alice.sui instead of 0x…. Two reads cover almost every task:

• Lookup — name → target address (audric.sui → its treasury/custody 0x…)
• Reverse lookup — address → its default name

Rules

1. A null result is a valid answer. A name can exist with no target address set — treat "no target" as "cannot pay this name", not an error.
2. Never guess an address from a name. If resolution returns nothing, stop and say so.
3. Prefer gRPC. Sui JSON-RPC is deactivated July 31, 2026 (mainnet) — do not build new resolution on suix_resolveNameServiceAddress.
4. Sending to a name? The t2000 wallet resolves SuiNS itself: t2 send 5 USDC alice.sui — no separate lookup step needed.

Resolve (gRPC — the current path)