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/StampWidget.xaml.cs

@@ -12,6 +12,8 @@ namespace Content.Client.Paper.UI;
 [GenerateTypedNameReferences]
 public sealed partial class StampWidget : PanelContainer
 {
+    private static readonly ProtoId<ShaderPrototype> PaperStamp = "PaperStamp";
+
     private StyleBoxTexture _borderTexture;
     private ShaderInstance? _stampShader;
 
@@ -42,7 +44,7 @@ public sealed partial class StampWidget : PanelContainer
         PanelOverride = _borderTexture;
 
         var prototypes = IoCManager.Resolve<IPrototypeManager>();
-        _stampShader = prototypes.Index<ShaderPrototype>("PaperStamp").InstanceUnique();
+        _stampShader = prototypes.Index(PaperStamp).InstanceUnique();
     }
 
     protected override void Draw(DrawingHandleScreen handle)