Move entity effects definitions to shared (#35614)

* Move entity effects to shared

* relocate spawning to server

* Generic version of EntityEffect for just raising event.

* genericise everything

* oops forgot to push you

* some condensation

* finish rebas

* unwhite the space

* oops forgot nuke

* bad rebase fix

* useless annotations begone

---------

Co-authored-by: EmoGarbage404 <retron404@gmail.com>

Content.Shared/EntityEffects/Effects/CreateEntityReactionEffect.cs

@@ -0,0 +1,26 @@
+using Robust.Shared.Prototypes;
+using Robust.Shared.Serialization.TypeSerializers.Implementations.Custom.Prototype;
+
+namespace Content.Shared.EntityEffects.Effects;
+
+[DataDefinition]
+public sealed partial class CreateEntityReactionEffect : EventEntityEffect<CreateEntityReactionEffect>
+{
+    /// <summary>
+    ///     What entity to create.
+    /// </summary>
+    [DataField(required: true, customTypeSerializer: typeof(PrototypeIdSerializer<EntityPrototype>))]
+    public string Entity = default!;
+
+    /// <summary>
+    ///     How many entities to create per unit reaction.
+    /// </summary>
+    [DataField]
+    public uint Number = 1;
+
+    protected override string? ReagentEffectGuidebookText(IPrototypeManager prototype, IEntitySystemManager entSys)
+        => Loc.GetString("reagent-effect-guidebook-create-entity-reaction-effect",
+            ("chance", Probability),
+            ("entname", IoCManager.Resolve<IPrototypeManager>().Index<EntityPrototype>(Entity).Name),
+            ("amount", Number));
+}