Summary

• Remove dead friend request / acquaintance role-switching links from the edit-friend template (these roles were removed in 4.0)
• Add an editable Username field so subscription usernames can be renamed
• Add Subscription::update_user_login() to rename the underlying taxonomy term
• Fix redirect after save to always point to the correct edit page (handles renames)
• Remove redundant "Type: Virtual User" and "Status: Subscription" rows from edit-friend page, move "Created" to bottom
• Remove role name chip from the frontend author header (always showed "Subscription")

Test plan

• Edit a subscription and verify the new Username field appears
• Change a subscription's username and save — verify it persists and the page redirects correctly
• Try renaming to an already-taken username — verify it doesn't overwrite
• Confirm the old "Send Friend Request" / "Accept Friend Request" / role-switching links no longer appear
• Verify "Type" and "Status" rows are gone from the edit page, and "Created" appears at the bottom
• Verify the frontend author header no longer shows a "Subscription" chip

Test in WordPress Playground