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/ModifyBloodLevel.cs

@@ -0,0 +1,17 @@
+using Content.Shared.FixedPoint;
+using Robust.Shared.Prototypes;
+
+namespace Content.Shared.EntityEffects.Effects;
+
+public sealed partial class ModifyBloodLevel : EventEntityEffect<ModifyBloodLevel>
+{
+    [DataField]
+    public bool Scaled = false;
+
+    [DataField]
+    public FixedPoint2 Amount = 1.0f;
+
+    protected override string? ReagentEffectGuidebookText(IPrototypeManager prototype, IEntitySystemManager entSys)
+        => Loc.GetString("reagent-effect-guidebook-modify-blood-level", ("chance", Probability),
+            ("deltasign", MathF.Sign(Amount.Float())));
+}