The two-phase save architecture was fundamentally broken: saveVmConnection()
was called inside createServer() BEFORE saveSpawnRecord() created the record,
so the merge-by-spawnId silently failed every time — resulting in records
with no connection data and `spawn ls` showing nothing.
Replace with atomic single-save: createServer() now returns VMConnection,
and the orchestrator calls saveSpawnRecord() once with connection data
included. Removes saveVmConnection(), getConnectionPath(),
mergeLastConnection(), and last-connection.json entirely.
Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
Co-authored-by: A <258483684+la14-1@users.noreply.github.com>
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