Method UpdateUserName

internal/identity/store.go:3106–3117

UpdateUserName persists a new display name on the user row and returns the updated User. Input validation (length, whitespace) is the caller's responsibility — this layer only enforces that the row exists.

(ctx context.Context, userID, name string)

// the caller's responsibility — this layer only enforces that the row
// exists.
func (s *Store) UpdateUserName(ctx context.Context, userID, name string) (*User, error) {
	u := &User{}
	err := s.pool.QueryRow(ctx,
		`UPDATE users SET name = $1 WHERE id = $2
		 RETURNING id, email, name, google_subject, created_at`,
		name, userID,
	).Scan(&u.ID, &u.Email, &u.Name, &u.GoogleSubject, &u.CreatedAt)
	if err != nil {
		return nil, err
	}
	return u, nil
}

// --- Session management ---