* [thread] Add rt_thread_close()
This patch introduces a new function `rt_thread_close()` to enhances the
usability and maintainability by providing a dedicated mechanism for
closing threads.
- A new function `rt_thread_close()` is added to the API, providing a
standardized approach for closing threads.
- The `rt_thread_close()` function removes a thread from the thread
queue, updates its status to indicate closure, and performs the thread
timer detaching which is a embedded timer in thread object.
- Additionally, the `rt_thread_detach()` function is modified to utilize
`rt_thread_close()` internally, streamlining the thread detachment
process.
Signed-off-by: Shell <smokewood@qq.com>