Questionnaire: Make summary page even more intuitive

[vietlx426]

Currently, when users click "View all responses" in the questionnaire module, they see a total count of responses but cannot distinguish between completed submissions and incomplete (in-progress) responses. This makes it difficult for instructors to understand the actual status of their questionnaire data at a glance.
Current Behavior
The interface displays only:

Proposed Solution
Add a detailed breakdown that shows both completed and incomplete responses:

Benefits

• Improved clarity: Users can immediately see how many responses are actually completed
• Better data insight: Instructors can track participation and completion rates
• Enhanced user experience: More informative interface without cluttering the UI

This change provides essential information that helps users better understand their questionnaire response data and make informed decisions about when to close a questionnaire or follow up with participants.
FYI: @mchurchward