fix: associate reflection fields with labels

[Aayush-Raj07022008]

What

Fixed the accessibility of the reflection fields by associating each label with its textarea and connecting the word-count hint using aria-describedby.

Fixes #120

How I tested it

• npm run lint — passed with 0 errors
• npm run build — passed
• git diff --check — passed

Checklist

• I was assigned the issue before I started
• npm run lint and npm run build pass locally
• The diff only touches what the issue asked for

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[github-actions]

📸 How this looks

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