* studio: humanize ETA display for long training runs
When training takes hours or days, the ETA displayed raw minutes
(e.g. '560m 50s'). This changes the format to:
- Under 1 hour: Xm Ys (unchanged)
- 1-24 hours: Xh Ym Zs
- Over 24 hours: Xd Xh Xm
* Fix formatDuration edge cases and consolidate duplicate for PR #4608
- Guard NaN/Infinity inputs with Number.isFinite() (matches formatNumber in same file)
- Add sub-minute branch so 30s displays as "30s" instead of "0m 30s"
- Accept undefined in type signature to match formatNumber pattern
- Remove duplicate formatDuration from history-card-grid.tsx and import the shared one
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Co-authored-by: Daniel Han <danielhanchen@gmail.com>