feat: rename to routers

src/core/express/normalizeRouterReturnable.ts

@@ -1,8 +1,8 @@
-import { ResponderReturnable } from '../../server.js';
+import { RouterReturnable } from '../../server.js';
 import jsxToSvg from '../node/jsxToSvg.js';
 
-export default async function normalizeResponderReturnable(
-  returnable: ResponderReturnable,
+export default async function normalizeRouterReturnable(
+  returnable: RouterReturnable,
 ) {
   const awaitedReturnable = await returnable;
   const svg = await jsxToSvg(awaitedReturnable);