Points for user helpers

See Points_for_user (database) for schema and RLS.

Balance is the sum of ledger points per user_id. Updates append a delta row; they do not mutate prior rows.

get_points_balance_for_user_id

• Args: client, user_id
• Returns: { status, msg, data: number }

get_points_for_user_by_user_id

• Args: client, user_id
• Returns: { status, msg, data: PointsForUser[] } — newest first

update_points_balance_for_user

• Args: client, user_id, balance, update_reason
• Behavior: Loads current sum, inserts one row with points = balance - current (skips insert when unchanged)
• Returns: { status, msg, data: { balance, entry } } — entry is null when balance unchanged

Requires platform superadmin (RLS on insert).