Harden item occurrence grounding

internal/modules/dnd/shared/matching_test.go

@@ -2,6 +2,32 @@ package shared
 
 import "testing"
 
+func TestComparisonKeyNormalizesDNDText(t *testing.T) {
+	if TextComparisonPolicy != "dnd.text_comparison.v1" {
+		t.Fatalf("TextComparisonPolicy = %q", TextComparisonPolicy)
+	}
+	for _, test := range []struct {
+		name  string
+		input string
+		want  string
+	}{
+		{name: "case", input: "Captain Vale", want: "captain vale"},
+		{name: "compatibility", input: "Ａｌｌｙ", want: "ally"},
+		{name: "whitespace", input: "  Mira\u2003Thorn ", want: "mira thorn"},
+		{name: "apostrophes", input: "O’Rin and OʼRin", want: "o'rin and o'rin"},
+		{name: "unicode composition", input: "  Cafe\u0301\u2003d’Or ", want: "café d'or"},
+	} {
+		t.Run(test.name, func(t *testing.T) {
+			if got := ComparisonKey(test.input); got != test.want {
+				t.Fatalf("ComparisonKey(%q) = %q, want %q", test.input, got, test.want)
+			}
+		})
+	}
+	if ComparisonKey("Mira Thorn") == ComparisonKey("Mira Thorne") {
+		t.Fatal("different names received the same comparison key")
+	}
+}
+
 func TestContainsTokenSequence(t *testing.T) {
 	tests := []struct {
 		name  string