Clarify that re-running the curl installer upgrades in place, and detect
an existing install so the script prints an Updating message.
Co-authored-by: Frank Vitrano <WHC2006@users.noreply.github.com>
Skip local path resolution when install.sh runs via bash <(curl ...),
so resolve_src falls through to cloning instead of aborting on /dev/fd.
Co-authored-by: Frank Vitrano <WHC2006@users.noreply.github.com>