BUG: profile diff approval not reflecting changes

Description

When a super user approves a profile diff, the changes are not reflected in the user's profile. For example, a profile diff was recently approved but the approved changes did not appear on the profile. The goal of this ticket is to fix the broken approval flow so that approved diffs correctly update the user profile.

Changes Requested

• Fix the approval flow so that when a profile diff is approved, the changes are applied to the user's profile.
• Verify the full flow: user submit → list diffs → approve → profile updated.
• Add or update tests to cover the approval flow.
• Fix any other related broken flows.