Switch from tosholi to pydantic for config loading #443
Description
Long term it is probably better to rely on pydantic + tomli/omli-w for config loading and type validation rather than tosholi.
tosholi also has some limitation w.r.t. resolving types such as the need for these noqas:
proxystore/proxystore/p2p/relay/config.py
Line 57 in 67ee939