Let the club logo fill more of its ring, match it in the control panel

Drops the inner padding on the logo image so it fills the circle right
up to the ring, rather than floating small in the middle of it -- most
visible on logos with generous internal whitespace (e.g. some SVGs).

The control panel's club-detail page now frames the logo the same way.
It doesn't get the page-wide --color-primary override the club's own
site uses (the panel must never dress itself up as the club), so the
ring colour is set as a locally-scoped custom property on just this
element instead.

templates/_club_base.html

@@ -39,7 +39,7 @@
             {# The ring is the club's own primary colour -- a plain frame around whatever crest they uploaded. #}
             <div class="avatar">
                 <div class="w-16 rounded-full bg-base-100 ring-2 ring-primary ring-offset-2 ring-offset-base-100">
-                    <img class="club-logo object-contain p-1" src="{{ club.logo.url }}" alt="{{ club.name }}">
+                    <img class="club-logo object-contain" src="{{ club.logo.url }}" alt="{{ club.name }}">
                 </div>
             </div>
         {% else %}