The preflight join carried "// Ensure the database exists on the running
instance" above a line that only builds a URL. No ensureDatabase() call has
ever followed it, so the comment described behavior the code does not have.
Replace it with why the call is absent: a joiner has no cluster of its own to
ensure, the owning process creates the database after its own start(), and
ensureDatabase() would throw here anyway because it requires `this.running` --
which the join path leaves false by design so stop() never reaps an instance
we did not start.
Also records the ordering assumption the path rests on: the owner publishes
runningInstances / writes postmaster.pid before its ensureDatabase() resolves,
so a joiner winning that window fails at the connection layer rather than
silently using a missing database.
Comment-only; no behavior change.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
e9537c9e85