Replace all raw string comparisons with StringKey, source generator that creates cache keys for all names for Gen7 plugin

Plugins/PkmnLib.Plugin.Gen7.SourceGen/EquatableArray.cs

@@ -0,0 +1,52 @@
+using System.Collections;
+
+namespace PkmnLib.Plugin.Gen7.SourceGen;
+
+/// <summary>
+/// An immutable array wrapper with sequence-based equality, so that incremental generator pipeline
+/// values containing collections cache correctly.
+/// </summary>
+public readonly struct EquatableArray<T> : IEquatable<EquatableArray<T>>, IReadOnlyList<T> where T : IEquatable<T>
+{
+    private readonly T[]? _array;
+
+    public EquatableArray(T[] array)
+    {
+        _array = array;
+    }
+
+    public int Count => _array?.Length ?? 0;
+
+    public T this[int index] => _array![index];
+
+    public bool Equals(EquatableArray<T> other)
+    {
+        if (Count != other.Count)
+            return false;
+        for (var i = 0; i < Count; i++)
+        {
+            if (!this[i].Equals(other[i]))
+                return false;
+        }
+        return true;
+    }
+
+    public override bool Equals(object? obj) => obj is EquatableArray<T> other && Equals(other);
+
+    public override int GetHashCode()
+    {
+        unchecked
+        {
+            var hash = 17;
+            for (var i = 0; i < Count; i++)
+            {
+                hash = hash * 31 + this[i].GetHashCode();
+            }
+            return hash;
+        }
+    }
+
+    public IEnumerator<T> GetEnumerator() => ((IEnumerable<T>)(_array ?? [])).GetEnumerator();
+
+    IEnumerator IEnumerable.GetEnumerator() => GetEnumerator();
+}