feat: unify recommend anonymous runtime guest auth

- Route recommended runtime launches through shared runtime guest token handling
- Extend recommend-page anonymous play beyond jump-hop
- Add regression coverage for runtime guest launch clients
- Update docs to reflect the full anonymous-play matrix

src/services/authService.ts

@@ -25,6 +25,7 @@ import type {
   AuthWechatStartResponse,
   LogoutResponse,
   PublicUserSearchResponse,
+  RuntimeGuestTokenResponse,
 } from '../../packages/shared/src/contracts/auth';
 import type { RedeemProfileReferralInviteCodeResponse } from '../../packages/shared/src/contracts/runtime';
 import {
@@ -61,6 +62,42 @@ const PUBLIC_AUTH_REQUEST_OPTIONS = {
   skipRefresh: true,
 } satisfies ApiRequestOptions;
 
+const runtimeGuestTokenCache: {
+  value: RuntimeGuestTokenResponse | null;
+} = {
+  value: null,
+};
+
+function isRuntimeGuestTokenFresh(response: RuntimeGuestTokenResponse | null) {
+  if (!response?.expiresAt) {
+    return false;
+  }
+  const expiresAtMs = Date.parse(response.expiresAt);
+  return Number.isFinite(expiresAtMs) && expiresAtMs - Date.now() > 15_000;
+}
+
+export function clearRuntimeGuestTokenCache() {
+  runtimeGuestTokenCache.value = null;
+}
+
+export async function ensureRuntimeGuestToken() {
+  if (isRuntimeGuestTokenFresh(runtimeGuestTokenCache.value)) {
+    return runtimeGuestTokenCache.value!;
+  }
+
+  const response = await requestJson<RuntimeGuestTokenResponse>(
+    '/api/auth/runtime-guest-token',
+    {
+      method: 'POST',
+    },
+    '获取匿名运行态身份失败',
+    PUBLIC_AUTH_REQUEST_OPTIONS,
+  );
+
+  runtimeGuestTokenCache.value = response;
+  return response;
+}
+
 const LAST_LOGIN_PHONE_STORAGE_KEY = 'genarrative:last-login-phone';
 
 export function normalizePhoneInput(phoneInput: string) {