Vendor .golangci.yml byte-identical from sneak/prompts at cc440118 and
move the Dockerfile lint phase to golangci-lint v2.14.0 by the digest
REPO_POLICIES.md names. Fix the code to that config with flags, help
text, output files, SQL and the order of steps unchanged; long
functions are split into named steps.
Judgement call: the extraction transaction is now rolled back on every
early return; the old deferred rollback missed most failures and could
dereference a nil transaction.
Thirteen //nolint directives (gosec, unconvert, mnd, unqueryvet), each
with its reason.
Model: opus-5-5