Fix PR 3 review findings [skip ci]

launcher/src/components/PlayerProfileModal.svelte

@@ -88,9 +88,11 @@
   }
 
   async function handleLikePost(post: UserPost) {
+    if (post.liked_by_me) return;
     try {
-      await invoke('like_user_post', { postId: post.id });
-      post.likes_count += 1;
+      const liked = await invoke<boolean>('like_user_post', { postId: post.id });
+      if (liked) post.likes_count += 1;
+      post.liked_by_me = true;
     } catch (e: any) {
       toast(e?.message ?? 'Failed to update like', 'error');
     }

launcher/src/pages/Quests.svelte

@@ -106,9 +106,9 @@
       return `${hours}h ${mins}m`;
     } else {
       const day = now.getUTCDay();
-      const daysUntilSunday = (7 - day) % 7 || 7;
-      const nextSunday = new Date(Date.UTC(now.getUTCFullYear(), now.getUTCMonth(), now.getUTCDate() + daysUntilSunday));
-      const diffMs = nextSunday.getTime() - now.getTime();
+      const daysUntilMonday = (8 - day) % 7 || 7;
+      const nextMonday = new Date(Date.UTC(now.getUTCFullYear(), now.getUTCMonth(), now.getUTCDate() + daysUntilMonday));
+      const diffMs = nextMonday.getTime() - now.getTime();
       const days = Math.floor(diffMs / (1000 * 60 * 60 * 24));
       const hours = Math.floor((diffMs % (1000 * 60 * 60 * 24)) / (1000 * 60 * 60));
       return `${days}d ${hours}h`;