fix(react): replace triple as-cast chain with Set-based type guard in groupExportsByKind

Author: ryanwaits

packages/react/src/components/shared.ts

@@ -17,16 +17,19 @@ export interface CategoryGroup {
   exports: SpecExport[];
 }
 
+const DISPLAY_KIND_SET: Set<string> = new Set(DISPLAY_KIND_ORDER);
+function isDisplayKind(kind: string): kind is DisplayKind {
+  return DISPLAY_KIND_SET.has(kind);
+}
+
 export function groupExportsByKind(exports: SpecExport[]): CategoryGroup[] {
   const groups = new Map<DisplayKind, SpecExport[]>();
 
   for (const exp of exports) {
-    const kind = exp.kind as string;
-    if (!(DISPLAY_KIND_ORDER as string[]).includes(kind)) continue;
-    const displayKind = kind as DisplayKind;
-    const list = groups.get(displayKind) || [];
+    if (!isDisplayKind(exp.kind)) continue;
+    const list = groups.get(exp.kind) || [];
     list.push(exp);
-    groups.set(displayKind, list);
+    groups.set(exp.kind, list);
   }
 
   return DISPLAY_KIND_ORDER.filter((kind) => groups.has(kind)).map((kind) => ({