When we register a volume without a plugin, we need to send a client RPC so that
the node fingerprint can be updated. The registered volume also needs to be
written to client state so that we can restore the fingerprint after a restart.
Co-authored-by: Daniel Bennett <dbennett@hashicorp.com>
store dynamic host volume creations in client state,
so they can be "restored" on agent restart. restore works
by repeating the same Create operation as initial creation,
and expecting the plugin to be idempotent.
this is (potentially) especially important after host restarts,
which may have dropped mount points or such.
also ensure that volume ID is uuid-shaped so user-provided input
like `id = "../../../"` which is used as part of the target directory
can not find its way very far into the volume submission process
