Add reusable CI preparation operations

preparation.go

@@ -0,0 +1,40 @@
+package releasekit
+
+import (
+	"context"
+
+	internalpreparation "gitea.maximumdirect.net/eric/ReleaseKit/internal/preparation"
+)
+
+// TaggedCheckoutRequest selects a stable tag and the full Git object ID
+// expected by an external build or CI event. An empty Remote selects origin.
+type TaggedCheckoutRequest struct {
+	RepositoryDir  string
+	Version        string
+	Remote         string
+	ExpectedCommit string
+}
+
+// PrepareTaggedCheckout fetches Version from Remote, verifies that its peeled
+// commit matches ExpectedCommit, and checks out that commit detached. This
+// operation mutates the selected local repository; use it for disposable
+// checkouts where tag-fetch and checkout conflicts can be resolved by the
+// caller. It does not publish a tag or hosted content.
+func PrepareTaggedCheckout(ctx context.Context, request TaggedCheckoutRequest) error {
+	return internalpreparation.PrepareTaggedCheckout(ctx, internalpreparation.TaggedCheckoutRequest{
+		RepositoryDir:  request.RepositoryDir,
+		Version:        request.Version,
+		Remote:         request.Remote,
+		ExpectedCommit: request.ExpectedCommit,
+	})
+}
+
+// PrepareBuildDependencies runs `go mod download` in repositoryDir with
+// workspace discovery disabled and the locally available compatible Go
+// toolchain selected. It may access module networks and updates the Go module
+// cache using the caller's Go proxy, private-module, credential, and cache
+// settings. If required checksums are missing, the Go command may update
+// go.sum. Cancellation and Go command failures are returned to the caller.
+func PrepareBuildDependencies(ctx context.Context, repositoryDir string) error {
+	return internalpreparation.PrepareBuildDependencies(ctx, repositoryDir)
+}