fix(src): replace AppRouteUserlandModule with looser type

closes #1006
addresses #1005

src/index.ts

@@ -11,6 +11,7 @@ import {
 } from 'node:http';
 
 import type { NextApiHandler } from 'next';
+import type { NextRequest } from 'next/server';
 
 // ? Next expects AsyncLocalStorage to be globally available IMMEDIATELY! So
 // ? this line should happen before any imports of Next.js packages.
@@ -137,7 +138,15 @@ export interface NtarhInitAppRouter<NextResponseJsonType = unknown>
    * documentation](https://nextjs.org/docs/app/building-your-application/routing/route-handlers)
    * for details.
    */
-  appHandler: import('next/dist/server/future/route-modules/app-route/module').AppRouteUserlandModule;
+  appHandler: Omit<
+    import('next/dist/server/future/route-modules/app-route/module').AppRouteUserlandModule,
+    keyof import('next/dist/server/future/route-modules/app-route/module').AppRouteHandlers
+  > & {
+    [key in keyof import('next/dist/server/future/route-modules/app-route/module').AppRouteHandlers]?: (
+      req: NextRequest,
+      context?: any
+    ) => any;
+  };
   pagesHandler?: undefined;
   /**
    * `params` is passed directly to the handler and represents processed dynamic

test/unit-index.test.ts

@@ -3,7 +3,7 @@ import { testApiHandler } from 'universe/index';
 
 import { parse, serialize } from 'cookie';
 import { cookies, headers } from 'next/headers';
-import { NextResponse } from 'next/server';
+import { NextResponse, type NextRequest } from 'next/server';
 
 import { withMockedOutput } from 'testverse/setup';
 
@@ -1442,6 +1442,29 @@ describe('::testApiHandler', () => {
         }
       });
     });
+
+    it('does not throw any AppRouteUserlandModule-related type errors', async () => {
+      expect.hasAssertions();
+
+      const appHandler = {
+        async GET(req: NextRequest, { params }: { params: { recipeId: string } }) {
+          const { recipeId } = params;
+          expect(req).toBeDefined();
+          expect(recipeId).toBe('1');
+          return NextResponse.json({});
+        }
+      };
+
+      await testApiHandler({
+        rejectOnHandlerError: true,
+        // This test "fails" if there is a TS error (caught by CI/linting)
+        appHandler,
+        params: { recipeId: '1' },
+        async test({ fetch }) {
+          await expect(fetch()).resolves.toBeDefined();
+        }
+      });
+    });
   });
 
   describe('<pages router>', () => {