refactor(commands): dedupe gateway self presence picker

src/commands/gateway-presence.ts

@@ -0,0 +1,27 @@
+export type GatewaySelfPresence = {
+  host?: string;
+  ip?: string;
+  version?: string;
+  platform?: string;
+};
+
+export function pickGatewaySelfPresence(presence: unknown): GatewaySelfPresence | null {
+  if (!Array.isArray(presence)) {
+    return null;
+  }
+  const entries = presence as Array<Record<string, unknown>>;
+  const self =
+    entries.find((e) => e.mode === "gateway" && e.reason === "self") ??
+    // Back-compat: older presence payloads only included a `text` line.
+    entries.find((e) => typeof e.text === "string" && String(e.text).startsWith("Gateway:")) ??
+    null;
+  if (!self) {
+    return null;
+  }
+  return {
+    host: typeof self.host === "string" ? self.host : undefined,
+    ip: typeof self.ip === "string" ? self.ip : undefined,
+    version: typeof self.version === "string" ? self.version : undefined,
+    platform: typeof self.platform === "string" ? self.platform : undefined,
+  };
+}