cleanup/refactory : Re-Generate Alpha Command

refactor: improve error handling, encapsulate logic, and streamline flow in rescaffold command

- Improved error handling by wrapping errors with `fmt.Errorf` and propagating them instead of using `log.Fatalf`. This ensures better debugging and more graceful error recovery.
- Encapsulated repeated logic such as directory changes, config loading, and path handling into dedicated helper functions, reducing redundancy and improving code readability.
- Ensured consistent logging: logging is reserved for informative messages like plugin migration steps, while error handling uses `fmt.Errorf` for consistency.
- Simplified control flow by removing redundant error checks and unnecessary logic, making the code easier to follow without altering functionality.
- Renamed methods to improve clarity and follow established naming conventions.
- Avoided unnecessary exports by keeping methods private where applicable.
- Ensured the refactored code is properly encapsulated under the command structure (`rescaffold`) as part of the appropriate command directory structure.

pkg/cli/alpha/generate.go

@@ -17,12 +17,13 @@ import (
 	log "github.com/sirupsen/logrus"
 
 	"github.com/spf13/cobra"
-	"sigs.k8s.io/kubebuilder/v4/pkg/rescaffold"
+
+	"sigs.k8s.io/kubebuilder/v4/pkg/command/generate"
 )
 
 // NewScaffoldCommand return a new scaffold command
 func NewScaffoldCommand() *cobra.Command {
-	opts := rescaffold.MigrateOptions{}
+	opts := generate.Generate{}
 	scaffoldCmd := &cobra.Command{
 		Use:   "generate",
 		Short: "Re-scaffold an existing Kuberbuilder project",
@@ -36,8 +37,8 @@ Then we will re-scaffold the project by Kubebuilder in the directory specified b
 			return opts.Validate()
 		},
 		Run: func(_ *cobra.Command, _ []string) {
-			if err := opts.Rescaffold(); err != nil {
-				log.Fatalf("Failed to rescaffold %s", err)
+			if err := opts.Generate(); err != nil {
+				log.Fatalf("Failed to command %s", err)
 			}
 		},
 	}