feat(framework): net 候选服务器轮询策略

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

cocoscreator_projects/framework-tests/net/reconnect.test.ts

@@ -0,0 +1,32 @@
+import { test } from 'node:test';
+import assert from 'node:assert/strict';
+import { ReconnectPolicy } from '../../YouleNexus/assets/framework/net/reconnect.ts';
+
+test('单服务器：失败永不轮换', () => {
+  const p = new ReconnectPolicy('ws://a', 3);
+  assert.equal(p.current(), 'ws://a');
+  for (let i = 0; i < 10; i++) assert.equal(p.onFailure(), 'ws://a');
+});
+
+test('多服务器：每 3 次失败轮换下一个', () => {
+  const p = new ReconnectPolicy(['ws://a', 'ws://b', 'ws://c'], 3);
+  assert.equal(p.onFailure(), 'ws://a'); // 1
+  assert.equal(p.onFailure(), 'ws://a'); // 2
+  assert.equal(p.onFailure(), 'ws://b'); // 3 → 轮换
+  assert.equal(p.onFailure(), 'ws://b'); // 4
+  assert.equal(p.onFailure(), 'ws://b'); // 5
+  assert.equal(p.onFailure(), 'ws://c'); // 6 → 轮换
+});
+
+test('reset 清零失败计数', () => {
+  const p = new ReconnectPolicy(['ws://a', 'ws://b'], 3);
+  p.onFailure(); p.onFailure();
+  p.reset();
+  assert.equal(p.onFailure(), 'ws://a'); // 计数从 1 起，未到 3，不轮换
+});
+
+test('setCurrent 切换到指定服务器（服务器切换指令）', () => {
+  const p = new ReconnectPolicy(['ws://a', 'ws://b'], 3);
+  p.setCurrent('ws://room1');
+  assert.equal(p.current(), 'ws://room1');
+});