install.ps1 wrote the marker on Windows and the Rust installer now writes it,
but install.sh -- the path every Mac and Linux CLI install takes -- never did.
A machine set up with install.sh therefore looked uninstalled to the desktop
app, which re-ran first-run bootstrap on every launch.
Stamp the same schema-v1 payload install.ps1 writes, from both the staged
`complete` stage and monolithic main(). An unresolvable HEAD skips the marker
rather than writing one the desktop validator rejects: absent reads as a clean
"bootstrap needed", malformed reads as a confusing half-state.
