test: add unit tests for TUI

[notgitika]

Description

WIP: do not merge

Related Issue

Closes #

Documentation PR

Type of Change

• Bug fix
• New feature
• Breaking change
• Documentation update
• Other (please describe): test

Testing

How have you tested the change?

• I ran npm run test:all
• I ran npm run typecheck
• I ran npm run lint
• If I modified src/assets/, I ran npm run test:update-snapshots and committed the updated snapshots

Checklist

• I have read the CONTRIBUTING document
• I have added any necessary tests that prove my fix is effective or my feature works
• I have updated the documentation accordingly
• I have added an appropriate example to the documentation to outline the feature, or no new docs are needed
• My changes generate no new warnings
• Any dependent changes have been merged and published

---

By submitting this pull request, I confirm that you can use, modify, copy, and redistribute this contribution, under the
terms of your choice.

[github-actions]

Coverage Report

Status	Category	Percentage	Covered / Total
🔵	Lines	38.79%	2495 / 6432
🔵	Statements	38.25%	2615 / 6835
🔵	Functions	41.64%	546 / 1311
🔵	Branches	43.23%	1630 / 3770

Generated in workflow #400 for commit 2652c18 by the Vitest Coverage Report Action