修复拼图生成前订阅授权

新增小程序原生订阅消息授权页，在用户点击后请求生成结果通知授权。

拼图 compile_puzzle_draft 前等待授权页返回或跳过后再发起生成 action。

移除 web-view message 订阅授权路径，改用 storage/hash 回写订阅结果。

补充订阅授权测试、文档和团队踩坑记录。

src/services/wechatMiniProgramSubscribe.ts

@@ -0,0 +1,160 @@
+import { isWechatMiniProgramRuntime } from './payment/paymentPlatform';
+
+const WECHAT_JS_SDK_URL = 'https://res.wx.qq.com/open/js/jweixin-1.6.0.js';
+const SUBSCRIBE_RESULT_HASH_KEY = 'wx_subscribe_result';
+const SUBSCRIBE_RESULT_TIMEOUT_MS = 30_000;
+
+function clearSubscribeResultHash() {
+  const rawHash = window.location.hash.replace(/^#/, '');
+  if (!rawHash.includes(`${SUBSCRIBE_RESULT_HASH_KEY}=`)) {
+    return;
+  }
+
+  const params = new URLSearchParams(rawHash);
+  params.delete(SUBSCRIBE_RESULT_HASH_KEY);
+  const nextHash = params.toString();
+  window.history.replaceState(
+    null,
+    '',
+    `${window.location.pathname}${window.location.search}${nextHash ? `#${nextHash}` : ''}`,
+  );
+}
+
+function readSubscribeResultFromHash() {
+  const value = new URLSearchParams(window.location.hash.replace(/^#/, '')).get(
+    SUBSCRIBE_RESULT_HASH_KEY,
+  );
+  if (!value) {
+    return null;
+  }
+  clearSubscribeResultHash();
+  return value;
+}
+
+function waitSubscribeResultFromHash(timeoutMs = SUBSCRIBE_RESULT_TIMEOUT_MS) {
+  const immediateResult = readSubscribeResultFromHash();
+  if (immediateResult) {
+    return Promise.resolve(immediateResult);
+  }
+
+  return new Promise<string | null>((resolve) => {
+    let timer: number | null = null;
+    const cleanup = () => {
+      window.removeEventListener('hashchange', handleHashChange);
+      window.removeEventListener('focus', handleResume);
+      window.removeEventListener('pageshow', handleResume);
+      document.removeEventListener('visibilitychange', handleResume);
+      if (timer !== null) {
+        window.clearTimeout(timer);
+      }
+    };
+    const finish = (result: string | null) => {
+      cleanup();
+      resolve(result);
+    };
+    const consume = () => {
+      const result = readSubscribeResultFromHash();
+      if (result) {
+        finish(result);
+        return true;
+      }
+      return false;
+    };
+    const handleHashChange = () => {
+      consume();
+    };
+    const handleResume = () => {
+      if (
+        typeof document !== 'undefined' &&
+        document.visibilityState === 'hidden'
+      ) {
+        return;
+      }
+      consume();
+    };
+
+    window.addEventListener('hashchange', handleHashChange);
+    window.addEventListener('focus', handleResume);
+    window.addEventListener('pageshow', handleResume);
+    document.addEventListener('visibilitychange', handleResume);
+    timer = window.setTimeout(() => finish(null), timeoutMs);
+  });
+}
+
+function loadWechatJsSdk() {
+  if (
+    !isWechatMiniProgramRuntime() ||
+    typeof window === 'undefined'
+  ) {
+    return Promise.reject(new Error('not_mini_program'));
+  }
+  if (window.wx?.miniProgram?.navigateTo) {
+    return Promise.resolve(window.wx);
+  }
+
+  return new Promise<NonNullable<Window['wx']>>((resolve, reject) => {
+    const existingScript = document.querySelector<HTMLScriptElement>(
+      `script[src="${WECHAT_JS_SDK_URL}"]`,
+    );
+    const complete = () => {
+      if (window.wx?.miniProgram?.navigateTo) {
+        resolve(window.wx);
+      } else {
+        reject(new Error('wechat_js_sdk_unavailable'));
+      }
+    };
+
+    if (existingScript) {
+      existingScript.addEventListener('load', complete, { once: true });
+      existingScript.addEventListener('error', () => reject(new Error('wechat_js_sdk_load_failed')), {
+        once: true,
+      });
+      complete();
+      return;
+    }
+
+    const script = document.createElement('script');
+    script.src = WECHAT_JS_SDK_URL;
+    script.async = true;
+    script.onload = complete;
+    script.onerror = () => reject(new Error('wechat_js_sdk_load_failed'));
+    document.head.appendChild(script);
+  });
+}
+
+export async function requestGenerationResultSubscribePermission() {
+  if (!isWechatMiniProgramRuntime() || typeof window === 'undefined') {
+    return false;
+  }
+
+  let wxBridge: NonNullable<Window['wx']>;
+  try {
+    wxBridge = await loadWechatJsSdk();
+  } catch {
+    return false;
+  }
+
+  const miniProgram = wxBridge.miniProgram;
+  if (!miniProgram || typeof miniProgram.navigateTo !== 'function') {
+    return false;
+  }
+
+  const requestId = `subscribe_generation_result_${Date.now()}`;
+  const navigated = await new Promise<boolean>((resolve) => {
+    miniProgram.navigateTo?.({
+      url: `/pages/subscribe-message/index?requestId=${encodeURIComponent(requestId)}&scene=generation-result`,
+      success() {
+        resolve(true);
+      },
+      fail() {
+        resolve(false);
+      },
+    });
+  });
+  if (!navigated) {
+    return false;
+  }
+  const resultPromise = waitSubscribeResultFromHash();
+  const result = await resultPromise;
+  return Boolean(result);
+}