All three UI variants stripped the displayed version at the FIRST
dash, assuming it was always the commit-hash separator build.sh
appends. A tag containing its own dash (e.g. v1.21-rc1) has that
dash earlier, so the splash screen silently dropped "-rc1" and
showed just "v1.21" — no way to tell an RC from the final release
on-device.
Strip at the LAST dash instead, since build.sh always appends the
commit hash as the final segment regardless of how many dashes the
tag itself has.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>