AI review:

Summary: Refactors the ratings GET endpoint to extract get_ratings_summary as a static method in preparation for FastAPI migration.
Changes

• Extracted logic into a static method get_ratings_summary(work_id)
• Returns a dict instead of serialized JSON string
• The GET method now calls the static method and wraps result in json.dumps()
  Potential Risks

1. No test updates visible: If existing tests call this endpoint and expect a JSON string response, they may fail. Check if tests need updating.
2. Internal usage: If any other code calls this method directly (unlikely given it's a page handler), it would now get a dict instead of a string.

This is the last of these needed for api.py