feat(cli): improve ipfs dag stat output UX

[lidel]

This PR is a follow-up for discussions triggered by https://github.com/ipfs/kubo/pull/10987.

Changes

• add TTY auto-detection for progress display (matching dag export)
• use single-line progress with carriage return instead of flooding
• show human-readable sizes alongside raw bytes in summary
• update --progress flag to be auto-detected by default

Demo

progress format: Fetched/Processed N blocks, M bytes (X MB) summary format: Total Size: 99 (99 B)