Fix the missing shield crest in the child's Quest Log header

Lit removes an attribute entirely when any interpolated part of it is
`nothing`, so `class="crest${away ? " away" : nothing}"` rendered a
present child's crest as a bare, unstyled span: an 11x51 sliver with a
16px black initial instead of the 96x110 brand-gradient shield. Use an
empty string for the present case, and widen the ring from 3px to the
spec's 4px.

Adds a jsdom test on the rendered crest classes (present and away) and
a stylesheet test pinning the PANEL-SPEC crest geometry, and rebuilds
the committed bundle.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

frontend/src/cards/quest-log.ts

@@ -378,7 +378,7 @@ const logStyles = css`
     flex: none;
     width: 96px;
     height: 110px;
-    padding: 3px;
+    padding: 4px;
     clip-path: ${unsafeCSS(SHIELD_CLIP)};
     background: rgba(255, 255, 255, 0.22);
   }
@@ -1938,7 +1938,7 @@ export class NestQuestQuestLogCard extends LitElement {
     const initial = (name?.charAt(0) || "?").toUpperCase();
     return html`
       <header class="header">
-        <span class="crest${away ? " away" : nothing}" aria-hidden="true">
+        <span class="crest${away ? " away" : ""}" aria-hidden="true">
           <span class="crest-face">
             <span class="initial">${initial}</span>
           </span>