Add back thread debug prints / add better debugging for startup process

A while ago I removed the printouts (now gated by the `Globals.DEBUG_THREAD_INFO` variable) which state when threads are started/stopped by the installer, to clean up the installer output.

However in cases where the installer does not start up properly, this can make it difficult to debug.

It may be better to enable this output, and/or improve the output so it is more clear what tasks will need to be completed during the startup process.

Also, there should be some debug output / handling if a thread hangs completely for whatever reason.

查找 Globals.DEBUG_THREAD_INFO 变量和安装程序的线程管理代码。该 issue 提到要重新添加线程启动/停止的调试输出，并改进启动过程的输出。此外，实现针对挂起线程的调试输出或处理。首先检查安装程序的启动序列和线程生命周期管理，以了解在何处插入日志记录和错误处理。

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