feat: add RCON password row to server detail page

l4d2web/templates/server_detail.html

@@ -11,6 +11,7 @@
   <dl class="server-info">
     <div><dt>Port</dt><dd><a href="steam://run/550//+connect%20{{ connect_host }}:{{ server.port }}">{{ server.port }}</a></dd></div>
     <div><dt>Blueprint</dt><dd>{% if blueprint %}<a href="/blueprints/{{ blueprint.id }}">{{ blueprint.name }}</a>{% endif %}</dd></div>
+    <div><dt>RCON Password</dt><dd><span class="password-mask" data-password-field="{{ server.id }}">••••••••••••</span><span class="password-value" data-password-field="{{ server.id }}" hidden>{{ server.rcon_password }}</span> <button class="link-button" data-password-toggle="{{ server.id }}" aria-label="Show RCON password">show</button></dd></div>
   </dl>
 
   <h2 class="section-title">Actions</h2>