Fix Daily Word stuck on "Loading…" (infinite reload loop)

The variant-watch $effect read `loading`, but load() flips `loading` false at
the end — which re-fired the effect, which called load() again, forever. The
board never rendered. Effect now tracks ONLY `variant`, so it loads once on
mount and once per variant toggle.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

frontend/src/lib/components/WordGame.svelte

@@ -1,5 +1,4 @@
 <script>
-  import { onMount } from 'svelte';
   import { getJSON } from '$lib/api.js';
 
   let { variant = '5', onstatus } = $props();
@@ -143,8 +142,12 @@
     else navigator.clipboard?.writeText(text).then(() => { copied = true; setTimeout(() => (copied = false), 1500); });
   }
 
-  onMount(load);
-  $effect(() => { variant; if (!loading) load(); }); // reload when the variant toggles
+  // Load on mount and whenever the variant toggles. Tracks ONLY `variant` — it
+  // must not depend on `loading`, or load()'s own loading flip would re-fire it.
+  $effect(() => {
+    variant;
+    load();
+  });
 </script>
 
 <svelte:window onkeydown={onKeydown} />