support user-related mode StaticHandler

[RanchoCooper]

Description:
If define a StaticHandler with user-related directory, then raise. For example

app = Vibora(router_strategy=RouterStrategy.CLONE,
             # NOTE. related path not work
             static=StaticHandler(paths=['~'],
                                  url_prefix='/static',
                                  max_cache_size=1024 * 1024))

it will raise StaticNotFound error

Improve:

• support user-related directory for StaticHandler