Add translator comments for several missing strings

[rrajput22]

Link to issue number:

Summary of the issue: Several translatable strings in source/controlTypes/role.py were missing translator comments. These strings are listed in tests/checkPot.py under EXPECTED_MESSAGES_WITHOUT_COMMENTS, meaning the NVDA team has specifically identified them as needing comments for proper localization.

Description of user facing changes: No user-facing functional changes. This PR only improves translator guidance for localization teams by adding context comments.

Description of developer facing changes: Added translator comments (#. Translators: …) above several role entries in role.py. These comments help translators understand the meaning and context of UI strings such as “border”, “filler”, “line”, “calendar”, “video”, “audio”, “data item”, and “header item”.

Description of development approach:

• Located missing strings listed in tests/checkPot.py
• Searched the codebase to identify where each string is defined
• Added translator comments using existing commenting conventions
• Ensured comments describe the UI element clearly and concisely
• Avoided changing any functionality or string identifiers
• Kept each change scoped and consistent with NVDA's documentation patterns

Testing strategy:

• Verified that each modified string is included in
• EXPECTED_MESSAGES_WITHOUT_COMMENTS
• Ensured translator comments follow existing patterns in role.py
• Confirmed that no behavior, values, or translations were altered
• Manual check through GitHub diff to ensure only comments were added

Known issues with pull request: None. Changes are strictly additive comments and do not impact runtime behavior.

Code Review Checklist:

• [x] Documentation:
  • Change log entry
  • User Documentation
  • Developer / Technical Documentation
  • Context sensitive help for GUI changes
• [x] Testing:
  • Unit tests
  • System (end to end) tests
  • Manual testing
• [x] UX of all users considered:
  • Speech
  • Braille
  • Low Vision
  • Different web browsers
  • Localization in other languages / culture than English
• [x] API is compatible with existing add-ons.
• [x] Security precautions taken.