The listener.Cleanup method will be called during
executor.Shutdown and route.restart, so it should serve
all kinds of listeners rather than a single tun device.
Currently listener.ReCreateTun will call it to handle
some internal affairs, This should be decoupled.
In this way, the cleanup tasks for data outside the
process life cycle that other listeners will add here
in the future will not be accidentally triggered
by configuring tun.
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