Add nonadmin backup delete cli support

[Joeavaikath]

• Add support for nonadmin backup delete

• Works by manually editing the nab spec to set the DeleteBackup field to true

• Add Makefile

[Copilot]

Pull Request Overview

This PR introduces CLI support for deleting non-admin backups, replaces the installation script with a Makefile, and updates documentation accordingly.

• Adds a delete command under cmd/non-admin/backup to mark backups for deletion.
• Introduces a Makefile for build, test, and install workflows and removes the old quick-create.sh.
• Updates README to use Makefile targets and removes the design document.

Reviewed Changes

Copilot reviewed 8 out of 9 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
quick-create.sh	Removed quick installation script in favor of Makefile.
kubectl-oadp-design.md	Removed outdated design document.
cmd/non-admin/backup/nonadminbackup_builder.go	Added getCurrentNamespace helper for namespace detection.
cmd/non-admin/backup/delete.go	Implemented delete command to set DeleteBackup field.
cmd/non-admin/backup/create.go	Removed duplicate getCurrentNamespace definition.
cmd/non-admin/backup/backup.go	Enabled delete subcommand and cleaned up command list.
README.md	Updated installation and development workflow to use Makefile.
Makefile	Added build, install, test, status, clean targets.

Comments suppressed due to low confidence (2)

cmd/non-admin/backup/backup.go:33

• [nitpick] The commented-out commands block clutters the code; consider removing unused commented lines or extracting them into documentation for clarity.

	c.AddCommand(

cmd/non-admin/backup/delete.go:1

• New delete functionality should be covered by unit or integration tests—consider adding tests for DeleteOptions.Run and deleteBackup.

package backup

[NicholasYancey]

Make file and delete.go looks good to merge.