fix(ui): сохранять точный выбор пира при экспорте WireGuard

lib/wg-export-peer.test.ts

@@ -0,0 +1,16 @@
+import { test } from "node:test"
+import assert from "node:assert/strict"
+import { selectWgExportPeer } from "./wg-export-peer"
+
+const peers = [{ id: "first", rosId: "*1" }, { id: "second", rosId: "*2" }]
+test("peer export resolves row and RouterOS IDs without changing an explicit selection", () => {
+  assert.equal(selectWgExportPeer(peers, "second"), peers[1])
+  assert.equal(selectWgExportPeer(peers, "*2"), peers[1])
+  assert.equal(selectWgExportPeer(peers, "missing"), undefined)
+  assert.equal(selectWgExportPeer(peers, ""), undefined)
+})
+test("peer export defaults only when no selection was provided", () => {
+  assert.equal(selectWgExportPeer(peers), peers[0])
+  assert.equal(selectWgExportPeer(peers, null), peers[0])
+  assert.equal(selectWgExportPeer([]), undefined)
+})