a27072b6d0
go.mod's 'go 1.25.0' directive (auto-set by go mod tidy because testcontainers-go v0.42.0 requires it) made the runner's bundled golangci-lint (built on Go 1.24) refuse to load the config. Pin to v2.12.2, the latest at time of writing, which is built on Go 1.25. Also: previous gofmt commit had subject 'style: gofmt -w' which our custom commitlint regex rejects (style isn't in the type allowlist). Squashed into this commit so the PR's commits all pass commitlint. Refs: M4.1