Improve progress output of oras backup/restore for better human readability

[FeynmanZhou]

What is the version of your ORAS CLI

oras v1.3.0-beta.3

What would you like to be added?

See an example progress output of oras backup:

$ oras backup docker.io/bitnami/kubectl --output kubectl.tar
Found 2 tag(s): v1.33.1, v1.33.2

Tag: v1.33.1
──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────
✓ Pulled  sha256:a86616b...   [        ............](8.12 MB/s) Pulling      106.0 MB  100%   11.0s
✓ Pulled  sha256:5dbdff1...     [        ............](8.12 MB/s) Pulling          6.69 KB  100%    6ms
✓ Pulled  sha256:2af8ed9...    [        ............](8.12 MB/s) Pulling       430 B  100%    6ms
✔ Tag v1.33.1 pulled with 0 referrer(s)

Tag: v1.33.2
──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────
✓ Pulled  sha256:e00d812...    [        ............](8.12 MB/s) Pulling     108.0 MB  100%   24.0s
✓ Pulled  sha256:322bd43...   [        ............](8.12 MB/s) Pulling         6.69 KB  100%    2ms
✓ Pulled  sha256:c8efec8...     [        ............](8.12 MB/s) Pulling     430 B  100%   11ms
✓ Pulled  sha256:9081a6f...    [        ............](8.12 MB/s) Pulling  529 B  100%   18ms
✔ Tag v1.33.2 pulled with 0 referrer(s)

Exporting backup archive...

The whole progress bar could be hided after the backup/restore process is done, it only prints out the summary as a result:

$ oras backup docker.io/bitnami/kubectl --output kubectl.tar
Backup completed in 27s: 2 tag(s) saved from docker.io/bitnami/kubectl. Written to kubectl.tar (214 MB)

Why is this needed for ORAS?

Issues with current progress bar (without Summary):

• Too Verbose and Overwhelming for Non-Experts:
  Dozens of lines for individual blobs, many repeating MIME types and digests. Hard to scan or extract key insights at a glance. Digest-heavy, JSON MIME-type output are great for debugging, but too low-level for end users.

• Hard to Validate:
  Users can't tell whether the backup/restore was complete or how many tags were transferred successfully. Which tag or repository the artifact belongs to.

$ oras backup docker.io/bitnami/kubectl --output kubectl.tar                    
Found 2 tag(s) in docker.io/bitnami/kubectl: v1.33.1, v1.33.2
✓ Pulled    application/vnd.docker.container.image.v1+json                                                        6.69/6.69 KB 100.00%   12ms
  └─ sha256:5dbdff18a5cf8f6a1b3fa6c8023f1d06b9533ca00ad8613be8d9b224968994f3                                                                 
✓ Pulled    application/vnd.docker.image.rootfs.diff.tar.gzip                                                       106/106 MB 100.00%    13s
  └─ sha256:a86616b90bad56f0f83f8c87e2dfe7e05e5242a89caa4e0238835fa52ef25585                                                                 
✓ Pulled    application/vnd.docker.container.image.v1+json                                                        6.69/6.69 KB 100.00%    1ms
  └─ sha256:322bd434c69032bddfb830e9c36c39f3efd987b693c311235c72618a3f654767                                                                 
✓ Pulled    application/vnd.docker.image.rootfs.diff.tar.gzip                                                       108/108 MB 100.00%    18s
  └─ sha256:e00d812ed2fb91179f71603b1314d730013904dd1f6fbeac538b9aac24d71e76                                                                 
✓ Pulled    application/vnd.docker.distribution.manifest.v2+json                                                    430/430  B 100.00%   17ms
  └─ sha256:2af8ed9feaeada845f4d60f1fe4db951df2e5334ea01bec4b5ef4f191ad20d65                                                                 
✓ Pulled    application/vnd.docker.distribution.manifest.v2+json                                                    430/430  B 100.00%   13ms
  └─ sha256:c8efec87588c7a2d84c760d54446b2e081e607a709f16f19283774d5612191b7                                                                 
✓ Pulled    application/vnd.docker.distribution.manifest.list.v2+json                                               529/529  B 100.00%   15ms
  └─ sha256:9081a6f83f4febf47369fc46b6f0f7683c7db243df5b43fc9defe51b0471a950                                                                 
Pulled tag v1.33.1 with 0 referrer(s)
✓ Exists    application/vnd.docker.distribution.manifest.list.v2+json                                               529/529  B 100.00%     0s
  └─ sha256:9081a6f83f4febf47369fc46b6f0f7683c7db243df5b43fc9defe51b0471a950                                                                 
Pulled tag v1.33.2 with 0 referrer(s)
Exporting to kubectl.tar
Exported to kubectl.tar (214 MB)
Successfully backed up 2 tag(s) from "docker.io/bitnami/kubectl" to "kubectl.tar" in 21s.

Are you willing to submit PRs to contribute to this feature?

• Yes, I am willing to implement it.