Support player sessions in admin logs and add test

Fix EventRan log type id
Make slipping low impact

Content.Server/Administration/Logs/AdminLogSystem.Json.cs

@@ -0,0 +1,86 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text.Json;
+using System.Text.Json.Serialization;
+using Content.Server.Administration.Logs.Converters;
+using Robust.Server.GameObjects;
+using Robust.Server.Player;
+using Robust.Shared.GameObjects;
+using Robust.Shared.IoC;
+
+namespace Content.Server.Administration.Logs;
+
+public partial class AdminLogSystem
+{
+    private static readonly JsonNamingPolicy NamingPolicy = JsonNamingPolicy.CamelCase;
+
+    // Init only
+    private JsonSerializerOptions _jsonOptions = default!;
+
+    private void InitializeJson()
+    {
+        _jsonOptions = new JsonSerializerOptions
+        {
+            PropertyNamingPolicy = NamingPolicy
+        };
+
+        foreach (var converter in _reflection.FindTypesWithAttribute<AdminLogConverterAttribute>())
+        {
+            var instance = _typeFactory.CreateInstance<JsonConverter>(converter);
+            _jsonOptions.Converters.Add(instance);
+        }
+
+        var converterNames = _jsonOptions.Converters.Select(converter => converter.GetType().Name);
+        _sawmill.Info($"Admin log converters found: {string.Join(" ", converterNames)}");
+    }
+
+    private (JsonDocument json, List<Guid> players, List<(int id, string? name)> entities) ToJson(
+        Dictionary<string, object?> properties)
+    {
+        var entities = new List<(int id, string? name)>();
+        var players = new List<Guid>();
+        var parsed = new Dictionary<string, object?>();
+
+        foreach (var key in properties.Keys)
+        {
+            var value = properties[key];
+            value = value switch
+            {
+                IPlayerSession player => new SerializablePlayer(player),
+                _ => value
+            };
+
+            var parsedKey = NamingPolicy.ConvertName(key);
+            parsed.Add(parsedKey, value);
+
+            EntityUid? entityId = properties[key] switch
+            {
+                EntityUid id => id,
+                IEntity entity => entity.Uid,
+                IPlayerSession {AttachedEntityUid: { }} session => session.AttachedEntityUid.Value,
+                IComponent component => component.OwnerUid,
+                _ => null
+            };
+
+            if (entityId is not { } uid)
+            {
+                continue;
+            }
+
+            var entityName = _entityManager.TryGetEntity(uid, out var resolvedEntity)
+                ? resolvedEntity.Name
+                : null;
+
+            entities.Add(((int) uid, entityName));
+
+            if (_entityManager.TryGetComponent(uid, out ActorComponent? actor))
+            {
+                players.Add(actor.PlayerSession.UserId.UserId);
+            }
+        }
+
+        return (JsonSerializer.SerializeToDocument(parsed, _jsonOptions), players, entities);
+    }
+
+}