Rebrand user-visible CLI text; add legacy fallbacks for keyring, cache dir and version prefix

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

version/version.go

@@ -11,7 +11,26 @@ import (
 	gvers "github.com/hashicorp/go-version"
 )
 
-const BoundaryPrefix = "Boundary v"
+const (
+	// BoundaryPrefix is the release version prefix used on the wire. It is
+	// kept as the emitted prefix so that this binary stays compatible with
+	// upstream HashiCorp Boundary peers that parse it.
+	BoundaryPrefix = "Boundary v"
+	// ThresholdPrefix is the release version prefix used for display and
+	// accepted additively when parsing.
+	ThresholdPrefix = "Threshold v"
+)
+
+// TrimReleasePrefix removes a leading (or embedded) "Boundary v" or
+// "Threshold v" release prefix from s, if present.
+func TrimReleasePrefix(s string) string {
+	for _, p := range []string{BoundaryPrefix, ThresholdPrefix} {
+		if idx := strings.Index(s, p); idx >= 0 {
+			return s[idx+len(p):]
+		}
+	}
+	return s
+}
 
 // Info
 type Info struct {
@@ -85,6 +104,7 @@ func (c *Info) Semver() *gvers.Version {
 func FromVersionString(s string) *Info {
 	s = strings.TrimSpace(s)
 	s = strings.TrimPrefix(s, BoundaryPrefix)
+	s = strings.TrimPrefix(s, ThresholdPrefix)
 	i := Info{}
 
 	// Get the revision
@@ -113,14 +133,26 @@ func FromVersionString(s string) *Info {
 	return &i
 }
 
+// FullVersionNumber returns the wire-format release version, which uses the
+// upstream "Boundary v" prefix for compatibility with peers.
 func (c *Info) FullVersionNumber(rev bool) string {
+	return c.fullVersionNumber(BoundaryPrefix, "Boundary", rev)
+}
+
+// DisplayVersionNumber returns the release version for display to users,
+// using the "Threshold v" prefix. Do not send this value over the wire.
+func (c *Info) DisplayVersionNumber(rev bool) string {
+	return c.fullVersionNumber(ThresholdPrefix, "Threshold", rev)
+}
+
+func (c *Info) fullVersionNumber(prefix, name string, rev bool) string {
 	var versionString bytes.Buffer
 
 	if Version == "unknown" && VersionPrerelease == "unknown" {
-		return "Boundary (version unknown)"
+		return name + " (version unknown)"
 	}
 
-	fmt.Fprintf(&versionString, "%s%s", BoundaryPrefix, c.Version)
+	fmt.Fprintf(&versionString, "%s%s", prefix, c.Version)
 	if c.VersionPrerelease != "" {
 		fmt.Fprintf(&versionString, "-%s", c.VersionPrerelease)
 	}