Move most references to PKMember.Name to go through helper extepsions for privacy

PluralKit.Bot/Utils/ModelUtils.cs

@@ -0,0 +1,13 @@
+using PluralKit.Core;
+
+namespace PluralKit.Bot
+{
+    public static class ModelUtils
+    {
+        public static string NameFor(this PKMember member, Context ctx) =>
+            member.NameFor(ctx.LookupContextFor(member));
+
+        public static string DisplayName(this PKMember member) =>
+            member.DisplayName ?? member.Name;
+    }
+}