Validate ShaderPrototype IDs (#38728)

* Convert all shader prototype string literals to protoids in overlays

* Convert more shader prototype literal strings to protoids

* Convert ValidatePrototypeId to ProtoId

* Later

Content.Client/Paper/UI/StampLabel.xaml.cs

@@ -10,6 +10,8 @@ namespace Content.Client.Paper.UI;
 [GenerateTypedNameReferences]
 public sealed partial class StampLabel : Label
 {
+    private static readonly ProtoId<ShaderPrototype> PaperStamp = "PaperStamp";
+
     /// A scale that's applied to the text to ensure it
     /// fits in the allowed space.
     private Vector2 _textScaling = Vector2.One;
@@ -26,7 +28,7 @@ public sealed partial class StampLabel : Label
         RobustXamlLoader.Load(this);
 
         var prototypes = IoCManager.Resolve<IPrototypeManager>();
-        _stampShader = prototypes.Index<ShaderPrototype>("PaperStamp").InstanceUnique();
+        _stampShader = prototypes.Index(PaperStamp).InstanceUnique();
     }
 
     protected override Vector2 MeasureOverride(Vector2 availableSize)