- Add QToolButton help icon (?) next to Project Mapping label
- Implement comprehensive tooltip explaining Project ID and Jira Key concepts
- Add inline validation to detect common mistake: entering issue keys (ABC-123) instead of project keys (ABC)
- Add 13 new i18n keys for help text in English, Vietnamese, and Japanese
- Add 15 comprehensive UX tests covering icon presence, tooltip content, validation logic, and accessibility
- Update jira-knowledge-guide.md with help icon reference and setup instructions
- Fix missing _on_paste method that was causing AttributeError
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
