feat(guild_chat): deck + replay attachments

Implement all five guild_chat attachment endpoints:
- add_deck: server looks up deck by (viewerId, format, deckNo) and snapshots
  the current state into a DECK-type chat message DeckPayload column.
- delete_deck: author OR leader/sub-leader may clear; returns refreshed
  deck_log. Extended IGuildChatMessageRepository.ClearDeckAsync with
  leaderOverride flag; added GetDeckMessagesAsync + GetByMessageIdAsync.
- add_replay: stores {"battle_id": N} in ReplayPayload; full shape is
  TODO(post-merge) pending replay-subsystem capture.
- replay_detail: returns the stored ReplayPayload as JsonElement passthrough.
- deck_log: returns all active DECK messages grouped by API-side Format string
  key ("1"=Rotation, "2"=Unlimited, "3"=PreRotation always present;
  "4"=Crossover, "5"=MyRotation only when non-empty).

Adds DeckLogDataDto (typed) for deck_log / delete_deck responses.
Replay response uses JsonElement passthrough (TODO(post-merge)).
8 new integration tests — all green. Full suite 1530/1530 pass.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

SVSim.EmulatedEntrypoint/Models/Dtos/Common/Guild/DeckLogDataDto.cs

@@ -0,0 +1,65 @@
+using MessagePack;
+using SVSim.Database.Enums;
+using SVSim.EmulatedEntrypoint.Extensions;
+using System.Text.Json.Serialization;
+using SVSim.EmulatedEntrypoint.Models.Dtos.Common;
+
+namespace SVSim.EmulatedEntrypoint.Models.Dtos.Common.Guild;
+
+/// <summary>
+/// Wire shape for a single entry in the deck_log bucket array, and for the inline
+/// `deck` object on a DECK-type chat message. Matches ChatMessageInfo.DeckLogData
+/// shape (Wizard/ChatMessageInfo.cs:DeckLogData).
+///
+/// Keys are a strict subset of what DeckData.Initialize() consumes:
+///   deck_format, message_id, delete_permission_exists, deck_no, deck_name,
+///   class_id, card_id_array, sleeve_id, leader_skin_id.
+/// </summary>
+[MessagePackObject]
+public class DeckLogDataDto
+{
+    /// <summary>API-side Format integer (via FormatJsonConverter).</summary>
+    [JsonPropertyName("deck_format"), Key("deck_format")]
+    [JsonConverter(typeof(FormatJsonConverter))]
+    public Format DeckFormat { get; set; }
+
+    /// <summary>Per-guild monotonic message_id of the DECK chat message that shared this deck.</summary>
+    [JsonPropertyName("message_id"), Key("message_id")]
+    [JsonConverter(typeof(StringifiedIntConverter))]
+    public int MessageId { get; set; }
+
+    /// <summary>Whether the viewing user may call /guild_chat/delete_deck for this entry.</summary>
+    [JsonPropertyName("delete_permission_exists"), Key("delete_permission_exists")]
+    public bool DeletePermissionExists { get; set; }
+
+    /// <summary>Deck slot number (within the format's personal deck list).</summary>
+    [JsonPropertyName("deck_no"), Key("deck_no")]
+    [JsonConverter(typeof(StringifiedIntConverter))]
+    public int DeckNo { get; set; }
+
+    /// <summary>Deck name as it was at share-time.</summary>
+    [JsonPropertyName("deck_name"), Key("deck_name")]
+    public string DeckName { get; set; } = string.Empty;
+
+    /// <summary>Class/craft id.</summary>
+    [JsonPropertyName("class_id"), Key("class_id")]
+    [JsonConverter(typeof(StringifiedIntConverter))]
+    public int ClassId { get; set; }
+
+    /// <summary>
+    /// Flat card list — card ids repeated by count, as DeckData.ParseCardIdList expects.
+    /// </summary>
+    [JsonPropertyName("card_id_array"), Key("card_id_array"),
+     JsonIgnore(Condition = JsonIgnoreCondition.Never)]
+    public List<long> CardIdArray { get; set; } = new();
+
+    /// <summary>Sleeve id at share-time.</summary>
+    [JsonPropertyName("sleeve_id"), Key("sleeve_id")]
+    [JsonConverter(typeof(StringifiedLongConverter))]
+    public long SleeveId { get; set; }
+
+    /// <summary>Leader skin id at share-time.</summary>
+    [JsonPropertyName("leader_skin_id"), Key("leader_skin_id")]
+    [JsonConverter(typeof(StringifiedIntConverter))]
+    public int LeaderSkinId { get; set; }
+}