refactor(rollback): validate description length before cluster reachability check

Move description length validation to the beginning of Run(), before
IsReachable(), so programmatic callers get an immediate validation
error instead of a potentially misleading cluster reachability failure.

Signed-off-by: MrJack <36191829+biagiopietro@users.noreply.github.com>

pkg/action/rollback.go

@@ -77,6 +77,10 @@ func NewRollback(cfg *Configuration) *Rollback {
 
 // Run executes 'helm rollback' against the given release.
 func (r *Rollback) Run(name string) error {
+	if descLen := utf8.RuneCountInString(r.Description); descLen > MaxDescriptionLength {
+		return fmt.Errorf("description must be %d characters or less, got %d", MaxDescriptionLength, descLen)
+	}
+
 	if err := r.cfg.KubeClient.IsReachable(); err != nil {
 		return err
 	}
@@ -121,10 +125,6 @@ func (r *Rollback) prepareRollback(name string) (*release.Release, *release.Rele
 		return nil, nil, false, errInvalidRevision
 	}
 
-	if descLen := utf8.RuneCountInString(r.Description); descLen > MaxDescriptionLength {
-		return nil, nil, false, fmt.Errorf("description must be %d characters or less, got %d", MaxDescriptionLength, descLen)
-	}
-
 	currentReleasei, err := r.cfg.Releases.Last(name)
 	if err != nil {
 		return nil, nil, false, err