Fix/qa defects df002 df011 (#9)

## Summary

What changed and why?

## Change Type

- [ ] Cowork feature
- [ ] Bug fix
- [ ] Core AI contribution
- [ ] Test / hardening
- [ ] Performance
- [ ] Documentation

## Related Work

Cowork Task:

Core Repo: http://34.143.229.138/gitea-admin/fsg-ai-core-assets

Core AI Issue:

Core Task:

Related PR:

## Scope

What is intentionally included?

What is intentionally NOT included?

## Validation

- [ ] Unit tests
- [ ] Integration tests
- [ ] Manual verification
- [ ] Regression check

Commands / evidence:

## Security Impact

Permission / credential / network / customer data impact:

## Compatibility

- [ ] No breaking change
- [ ] Breaking change documented

## Reviewer Notes

Anything Cowork reviewers should pay attention to.

---------

Co-authored-by: thanhnv <thanhnv.ip@gmail.com>
Co-authored-by: Vu Dam Tuan <vudt15@fpt.com>
Reviewed-on: #9

presentation/shell/rail_metrics.py

@@ -13,7 +13,7 @@ from PySide6.QtWidgets import QStyledItemDelegate
 # ---- kích thước ---------------------------------------------------------
 _NAV_EXPANDED_WIDTH = 150
 _NAV_COLLAPSED_WIDTH = 54
-_NAV_ROW_INSET = 4
+_NAV_ROW_INSET = 8
 _NAV_ROW_GAP = 6
 _NAV_MIN_WIDTH = 132
 _NAV_MAX_SHARE = 0.22