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

PluralKit.Core/Models/MemberId.cs

@@ -20,5 +20,7 @@
         public static bool operator !=(MemberId left, MemberId right) => !left.Equals(right);
 
         public int CompareTo(MemberId other) => Value.CompareTo(other.Value);
+        
+        public override string ToString() => $"Member #{Value}";
     }
 }

PluralKit.Core/Models/ModelExtensions.cs

@@ -0,0 +1,8 @@
+namespace PluralKit.Core
+{
+    public static class ModelExtensions
+    {
+        public static string NameFor(this PKMember member, LookupContext ctx) => 
+            member.NamePrivacy.CanAccess(ctx) ? member.Name : member.DisplayName ?? member.Name;
+    }
+}

PluralKit.Core/Models/SwitchId.cs

@@ -20,5 +20,7 @@
         public static bool operator !=(SwitchId left, SwitchId right) => !left.Equals(right);
 
         public int CompareTo(SwitchId other) => Value.CompareTo(other.Value);
+        
+        public override string ToString() => $"Switch #{Value}";
     }
 }

PluralKit.Core/Models/SystemId.cs

@@ -20,5 +20,7 @@
         public static bool operator !=(SystemId left, SystemId right) => !left.Equals(right);
 
         public int CompareTo(SystemId other) => Value.CompareTo(other.Value);
+
+        public override string ToString() => $"System #{Value}";
     }
 }