Installs PostgreSQL with the machine's own package manager when it has
none (initdb with password auth on the RHEL family, whose default is
ident), creates the llmgw role and database with a generated password
kept in /etc/llmgw/secrets/store-dsn, and checks the address connects.
On a machine already on SQLite it stops the gateway, copies the store
so accounts and keys survive, points auth.store at the new address and
starts it again. A move that fails starts the gateway on SQLite again.
server.yaml is edited as text so its comments survive, and kept beside
it. A PostgreSQL init did not install is not resized: it may serve
something else. It refuses to move one PostgreSQL store into another.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
