Rename data-ss-tpl attribute to data-ss-template

Spell out the abbreviation in the template marker attribute too, matching the
complete-words convention applied to the variables.

https://claude.ai/code/session_01XzhXvMvw42CQGc9kmin3GS

games/static/js/search_select.js

@@ -79,7 +79,7 @@
     // ── Clone a server-rendered <template> prototype by name. The server emits
     //    the mode-appropriate prototypes, so the JS never names a class. ──
     function cloneTemplate(name) {
-      var template = container.querySelector('template[data-ss-tpl="' + name + '"]');
+      var template = container.querySelector('template[data-ss-template="' + name + '"]');
       return template
         ? template.content.firstElementChild.cloneNode(true)
         : null;