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>

internal/server/worker_list.go

@@ -9,7 +9,6 @@ import (
 	stderrors "errors"
 	"fmt"
 	"math/big"
-	"strings"
 
 	"github.com/hashicorp/boundary/internal/daemon/controller/handlers"
 	"github.com/hashicorp/boundary/internal/event"
@@ -141,10 +140,7 @@ workerLoop:
 		}
 		if len(features) > 0 {
 			versionString := worker.ReleaseVersion
-			idx := strings.Index(versionString, version.BoundaryPrefix)
-			if idx >= 0 {
-				versionString = versionString[idx+len(version.BoundaryPrefix):]
-			}
+			versionString = version.TrimReleasePrefix(versionString)
 			nodeVersion, err := gvers.NewVersion(versionString)
 			if err != nil {
 				// Emit error and continue, as we might still find a different worker