Minor fixes across the club dashboard

We went through the club admin pages one at a time — teams, people, trial sessions, events, volunteer roles, lists, settings.

The change that matters: a form that will not save now marks the field, says why, and keeps what you had typed. Several were quietly discarding work when they failed.

Club settings became one card with six tabs rather than a long scroll, and the Save button sits at the end of the tab it saves.

We also found a stray character in the page source that had swallowed 120 closing brackets, leaving parts of a few admin pages not rendering at all. Fixed, and we now check what a page actually emits rather than what we assume it does.