Add cloudberry-backup ASF release script

[tuhaihe]

closes: #ISSUE_Number

---

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[tuhaihe]

workdir/cbdb/release                                                                                                           
▶ ./cloudberry-backup-release.sh --stage \
◀ --tag 2.1.0-incubating-rc1 \
◀ --repo ./cloudberry-backup \
◀ --gpg-user djwang@apache.org

=================================================================
>> Platform and Tool Detection
=================================================================
Platform detected: macOS

[OK] SHA-512 tool: sha512sum
[OK] Tar tool: gtar (GNU tar)
[OK] GPG tool: gpg 2.4.9
[OK] XML tool: xmllint

Press Enter or type y/yes to continue, or 'n' to exit: y

=================================================================
>> Validating Version Consistency
=================================================================
Version validation strategy:
  Tag: 2.1.0-incubating-rc1
  Base version (for source files): 2.1.0
Version consistency verified
    Release Tag   : 2.1.0-incubating-rc1
    Base Version  : 2.1.0
    VERSION file  : 2.1.0

Press Enter or type y/yes to continue, or 'n' to exit: y

=================================================================
>> Checking the state of the Tag
=================================================================
INFO: Tag '2.1.0-incubating-rc1' does not yet exist. It will be created during staging.

Press Enter or type y/yes to continue, or 'n' to exit: y

=================================================================
>> Checking GIT_USER_NAME and GIT_USER_EMAIL values
=================================================================
Git User Info:
    user.name     : Dianjin Wang
    user.email    : wangdianjin@gmail.com

=================================================================
>> Staging release: 2.1.0-incubating-rc1
=================================================================
You are about to create tag '2.1.0-incubating-rc1'. Continue? [y/N] y

Tag Summary
2.1.0-incubating-rc1 (tag object): a4ac52ee0139a60c2bcf707c4b34e994bc63439e
    Points to commit: e9c49746cefb14629b66f047002a4ef59700aeae
e9c49746  (HEAD -> main, tag: 2.1.0-incubating-rc1, origin/main, origin/HEAD)

Press Enter or type y/yes to continue, or 'n' to exit: y

=================================================================
>> Creating Source Tarball
=================================================================
Cleaning macOS extended attributes from extracted files...
[OK] Extended attributes cleaned using xattr
[OK] macOS-specific files removed
Using GNU tar for cross-platform compatibility...
INFO: macOS detected - applied extended attribute cleanup and GNU tar
Archive saved to: apache-cloudberry-backup-2.1.0-incubating-rc1-src.tar.gz
Verifying tarball does not contain macOS-specific files...
[OK] Tarball verified clean of macOS-specific files
Checking for extended attribute headers in tarball...
[OK] No extended attribute headers detected in tarball (GNU tar used)

Press Enter or type y/yes to continue, or 'n' to exit: y

=================================================================
>> Generating SHA-512 Checksum
=================================================================

Generating SHA-512 checksum
Checksum saved to: apache-cloudberry-backup-2.1.0-incubating-rc1-src.tar.gz.sha512

Press Enter or type y/yes to continue, or 'n' to exit: y

=================================================================
>> Signing with GPG key: djwang@apache.org
=================================================================

Signing tarball with GPG key: djwang@apache.org
GPG signature saved to: apache-cloudberry-backup-2.1.0-incubating-rc1-src.tar.gz.asc

=================================================================
>> Moving Artifacts to /Users/djwang/workdir/cbdb/release/artifacts
=================================================================

Moving release artifacts to: /Users/djwang/workdir/cbdb/release/artifacts
apache-cloudberry-backup-2.1.0-incubating-rc1-src.tar.gz -> /Users/djwang/workdir/cbdb/release/artifacts/apache-cloudberry-backup-2.1.0-incubating-rc1-src.tar.gz
apache-cloudberry-backup-2.1.0-incubating-rc1-src.tar.gz.sha512 -> /Users/djwang/workdir/cbdb/release/artifacts/apache-cloudberry-backup-2.1.0-incubating-rc1-src.tar.gz.sha512
apache-cloudberry-backup-2.1.0-incubating-rc1-src.tar.gz.asc -> /Users/djwang/workdir/cbdb/release/artifacts/apache-cloudberry-backup-2.1.0-incubating-rc1-src.tar.gz.asc

Press Enter or type y/yes to continue, or 'n' to exit: y

=================================================================
>> Verifying sha512 (/Users/djwang/workdir/cbdb/release/artifacts/apache-cloudberry-backup-2.1.0-incubating-rc1-src.tar.gz.sha512) Release Artifact
=================================================================
apache-cloudberry-backup-2.1.0-incubating-rc1-src.tar.gz: OK

Press Enter or type y/yes to continue, or 'n' to exit: y

=================================================================
>> Verifying GPG Signature (/Users/djwang/workdir/cbdb/release/artifacts/apache-cloudberry-backup-2.1.0-incubating-rc1-src.tar.gz.asc) Release Artifact
=================================================================
gpg: Signature made Fri Feb 27 18:10:08 2026 CST
gpg:                using RSA key 9A36AA272348A207E193A49C500708B75754FB7C
gpg: Good signature from "Dianjin Wang (for apache cloudberry release) <djwang@apache.org>" [ultimate]

Press Enter or type y/yes to continue, or 'n' to exit: y

=================================================================
>> Release candidate for 2.1.0-incubating-rc1 staged successfully
=================================================================                                                                                                     

workdir/cbdb/release                                                                                                           
▶ ls artifacts 
apache-cloudberry-backup-2.1.0-incubating-rc1-src.tar.gz
apache-cloudberry-backup-2.1.0-incubating-rc1-src.tar.gz.asc
apache-cloudberry-backup-2.1.0-incubating-rc1-src.tar.gz.sha512