fix(ask): prototype 拦截器替代 waterfall hook + TG 原生按钮作答

根因：dsh 0.1.5-rc.1 把 'user-questions/request' waterfall 分发到
per-fiber events 注册表，其他 fiber 的 ctx.on 监听（含本插件）永远收不到
分发（实测 root/global/agent 作用域监听全部落空）。

修复：包装 UserQuestionService.prototype.ask（类跨实例共享），无论哪个
fiber/实例发起的 ask 都能拦截到 agent+questions；TG 答案与原 ask 竞速，
保留 dual-path 语义；stop 时恢复原型，热重载不叠加。

功能（应用户要求）：
- 提问前显式发送预告文本消息
- 选项改用 TG 原生 inline keyboard 按钮（单选即点即答，多选带提交键）
- 文本作答保留并与按钮作答合并，逐题累计、齐题自动提交
- 附带修复：Telegram API 调用加 15s 客户端超时（代理挂死会卡死通知队列）

Co-authored-by: Shirobana Agent Bot <tg-bridge>

src/client.ts

@@ -153,12 +153,17 @@ export class TelegramClient implements TelegramClientLike {
     return message.split(this.token).join('***')
   }
 
-  private async call<T>(method: string, body?: Record<string, unknown>): Promise<T> {
+  private async call<T>(method: string, body?: Record<string, unknown>, timeoutMs = 15_000): Promise<T> {
     const url = `${this.baseUrl}/bot${this.token}/${method}`
     try {
       const init: RequestInit = {
         method: 'POST',
         headers: { 'Content-Type': 'application/json' },
+        // Without a client-side timeout a stalled proxy connection hangs the
+        // request forever — and the serialized notice queue wedges behind it,
+        // silently swallowing every later tool/ask notice. TimeoutError is
+        // caught below and surfaces as a normal (retryable) failure.
+        signal: AbortSignal.timeout(timeoutMs),
       }
       if (body !== undefined) {
         init.body = JSON.stringify(body)
@@ -187,7 +192,8 @@ export class TelegramClient implements TelegramClientLike {
     if (offset !== undefined) {
       body.offset = offset
     }
-    return this.call<TelegramUpdate[]>('getUpdates', body)
+    // Long-poll: client-side abort must outlive the server-side hold.
+    return this.call<TelegramUpdate[]>('getUpdates', body, this.pollingTimeoutSec * 1000 + 10_000)
   }
 
   async sendMessage(