Polish: daily reward via celebration overlay + premium chat to recipient

- Daily reward now routes through the global CelebrationOverlay: new "daily"
  variant + coins count-up; claiming closes the daily modal and fires
  celebrate({variant:"daily", coins}). Unifies the "you earned X" moment.
- Premium (pro) gold chat is now visible to the OTHER player: ChatMessage gains
  senderPro; server resolves each participant's plan once (SocialService.IsPro)
  and stamps it on ChatMessageDto; ChatScreen styles incoming bubbles with
  .premium-chat when senderPro. Mock marks ~half its friends pro so it's visible
  offline too.

Verified: tsc + next build + dotnet build all pass.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

server/src/Hokm.Server/Social/SocialModels.cs

@@ -24,6 +24,7 @@ public class ChatMessageDto
     public bool FromMe { get; set; }
     public string Text { get; set; } = "";
     public long Ts { get; set; }
+    public bool SenderPro { get; set; }
 }
 
 public class ConversationDto

server/src/Hokm.Server/Social/SocialService.cs

@@ -265,7 +265,9 @@ public class SocialService
             .OrderBy(m => m.CreatedAt).ToListAsync();
         var unread = msgs.Where(m => m.UserId == peerId && m.PeerId == uid && !m.ReadByPeer).ToList();
         if (unread.Count > 0) { unread.ForEach(m => m.ReadByPeer = true); await _db.SaveChangesAsync(); }
-        return msgs.Select(m => ToDto(m, uid)).ToList();
+        // Resolve each participant's plan once so premium (pro) senders show gold.
+        bool uidPro = await IsPro(uid), peerPro = await IsPro(peerId);
+        return msgs.Select(m => ToDto(m, uid, m.UserId == uid ? uidPro : peerPro)).ToList();
     }
 
     public async Task<ChatMessageDto> Send(string uid, string peerId, string text)
@@ -274,14 +276,24 @@ public class SocialService
         _db.Messages.Add(m);
         await _db.SaveChangesAsync();
         await _hub.Clients.User(peerId).SendAsync("chat", new { peerId = uid });
-        return ToDto(m, uid);
+        return ToDto(m, uid, await IsPro(uid));
     }
 
-    private static ChatMessageDto ToDto(MessageRow m, string uid) => new()
+    /// <summary>True when the user has an active premium (pro) plan.</summary>
+    private async Task<bool> IsPro(string userId)
+    {
+        var row = await _db.Profiles.FindAsync(userId);
+        if (row == null) return false;
+        var p = JsonSerializer.Deserialize<ProfileDto>(row.Json, JsonOpts.Default);
+        return p?.Plan == "pro";
+    }
+
+    private static ChatMessageDto ToDto(MessageRow m, string uid, bool senderPro = false) => new()
     {
         Id = m.Id.ToString(),
         FromMe = m.UserId == uid,
         Text = m.Text,
         Ts = new DateTimeOffset(m.CreatedAt).ToUnixTimeMilliseconds(),
+        SenderPro = senderPro,
     };
 }