This change reimplements run over the kurtosis SDK instead of shelling
out to the CLI tool, which fixes potential consistency problems with
other uses of the SDK.

Additionally, we split the endpoint detection logic into a separate
entity (will make it a separate package a bit later), and improve the
host handling part by no longer assuming reachability on localhost
(implicitly assuming Docker backend). This is a step toward supporting
k8s backend transparently.