feat: import messages from go version

Catalogger.GoImporter/Models.cs

@@ -14,6 +14,7 @@
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
 using NodaTime;
+using Remora.Discord.API.Objects;
 using J = System.Text.Json.Serialization.JsonPropertyNameAttribute;
 
 // ReSharper disable NotAccessedPositionalProperty.Global
@@ -45,3 +46,22 @@ public record GuildsExport(
     List<GoInvite> Invites,
     List<GoWatchlistEntry> Watchlist
 );
+
+public record GoMessage(
+    [property: J("MsgID")] ulong Id,
+    [property: J("UserID")] ulong UserId,
+    [property: J("ChannelID")] ulong ChannelId,
+    [property: J("ServerID")] ulong GuildId,
+    string Content,
+    string Username,
+    string? Member,
+    string? System,
+    GoMetadata? Metadata
+);
+
+public record GoMetadata(
+    [property: J("UserID")] ulong? UserId,
+    string? Username,
+    string? Avatar,
+    EmbedField[]? Embeds
+);