fix(sync): не считать сервис с одним IP резервированием

В payload для VPS Tracker lbMode не отдаём без пула уникальных IP; в UI показываем без резервирования вместо Round robin.

Co-authored-by: Cursor <cursoragent@cursor.com>

apps/api/test/vps-tracker-sync.test.ts

@@ -6,6 +6,7 @@ import {
 import {
   resolveBindingIpsForSync,
   resolveLbModeForSync,
+  effectiveLbModeForSync,
 } from "../src/services/vps-tracker-sync.js";
 
 function binding(
@@ -183,6 +184,35 @@ describe("resolveLbModeForSync", () => {
   });
 });
 
+describe("effectiveLbModeForSync", () => {
+  it("omits mode when unique origin IPs are below two", () => {
+    expect(
+      effectiveLbModeForSync("round_robin", "failover", ["203.0.113.10"]),
+    ).toBeUndefined();
+    expect(
+      effectiveLbModeForSync("round_robin", "failover", [
+        "203.0.113.10",
+        "203.0.113.10",
+      ]),
+    ).toBeUndefined();
+  });
+
+  it("emits configured mode when the service has a pool", () => {
+    expect(
+      effectiveLbModeForSync("failover", "round_robin", [
+        "203.0.113.10",
+        "203.0.113.20",
+      ]),
+    ).toBe("failover");
+    expect(
+      effectiveLbModeForSync("off", "weighted", [
+        "203.0.113.10",
+        "198.51.100.1",
+      ]),
+    ).toBe("weighted");
+  });
+});
+
 describe("cfdmBindingSyncItemSchema lbMode", () => {
   const base = {
     bindingId: 1,