Improve nomenclature of ES6 TypeScript defs default export

Author: jnickg

test/other/embind_tsgen_es6.d.ts

@@ -110,5 +110,4 @@ interface EmbindModule {
   wstring_test(_0: string): string;
 }
 export type MainModule = WasmModule & EmbindModule;
-export type MainModuleFunctor = (options?: unknown) => Promise<MainModule>;
-export default MainModuleFunctor;
+export default function MainModuleFactory (options?: unknown): Promise<MainModule>;

tools/emscripten.py

@@ -632,8 +632,7 @@ def create_tsd(metadata, embind_tsd):
     export_interfaces += ' & EmbindModule'
   out += f'export type MainModule = {export_interfaces};\n'
   if settings.EXPORT_ES6 and settings.MODULARIZE:
-    out += 'export type MainModuleFunctor = (options?: unknown) => Promise<MainModule>;\n'
-    out += 'export default MainModuleFunctor;\n'
+    out += 'export default function MainModuleFactory (options?: unknown): Promise<MainModule>;\n'
   return out