Fix an annoying TypeScript error

Apparently, TypeScript can't deal with default values for parameters
with inferred types:
microsoft/TypeScript#29049

src/pages/instrument.tsx

@@ -5,10 +5,10 @@ import React, { Suspense, useEffect, useState } from "react";
 import { getInstrumentById } from "#api";
 import NotFound from "#src/pages/404";
 import type { IInstrument } from "#src/types";
-import { lazy } from "#src/utils";
+import { lazyNamed } from "#src/utils";
 
-const Instrument = lazy(() => import("#layouts/Instrument"), "Instrument");
-const InstrumentForm = lazy(
+const Instrument = lazyNamed(() => import("#layouts/Instrument"), "Instrument");
+const InstrumentForm = lazyNamed(
   () => import("#layouts/InstrumentForm"),
   "InstrumentForm"
 );

src/utils.ts

@@ -1,18 +1,17 @@
-import { lazy as reactLazy } from "react";
+import { lazy } from "react";
 import type { ComponentType, LazyExoticComponent } from "react";
 
 /**
- * Lazily import a named or default exported component
+ * Lazily import a named exported component
  *
- *     const Named = lazy(() => import("./Named"), "Named");
- *     const Default = lazy(() => import("./Default")); // Omit 2nd argument
+ *     const Component = lazyNamed(() => import("./Component"), "Component");
  */
 // eslint-disable-next-line @typescript-eslint/no-explicit-any
-export function lazy<T extends ComponentType<any>, K extends string>(
+export function lazyNamed<T extends ComponentType<any>, K extends string>(
   factory: () => Promise<{ [key in K]: T }>,
-  exportedName: K = "default"
+  exportedName: K
 ): LazyExoticComponent<T> {
-  return reactLazy(async () => ({
+  return lazy(async () => ({
     // NOTE This dynamic property access breaks tree shaking for the imported
     // module! That isn't impacting this site's bundles though, since we only
     // export one component per module.