feat: implement error boundaries for improved error handling across routes

app/routes/_admin.lg-admin._dashboard.contents.update.$slug.tsx

@@ -1,3 +1,5 @@
+import { isRouteErrorResponse } from 'react-router'
+
 import { getNewsBySlug } from '~/apis/common/get-news-by-slug'
 import { handleCookie } from '~/libs/cookies'
 import { FormContentsPage } from '~/pages/form-contents'
@@ -13,6 +15,35 @@ export const loader = async ({ request, params }: Route.LoaderArgs) => {
   return { newsData }
 }
 
+export const ErrorBoundary = ({ error }: Route.ErrorBoundaryProps) => {
+  let message = 'Oops!'
+  let details = 'An unexpected error occurred.'
+  let stack: string | undefined
+
+  if (isRouteErrorResponse(error)) {
+    message = error.status === 404 ? '404' : 'Error'
+    details =
+      error.status === 404
+        ? 'The requested page could not be found.'
+        : error.statusText || details
+  } else if (import.meta.env.DEV && error && error instanceof Error) {
+    details = error.message
+    stack = error.stack
+  }
+
+  return (
+    <div className="container mx-auto p-4">
+      <h1>{message}</h1>
+      <p>{details}</p>
+      {stack && (
+        <pre className="w-full p-4 whitespace-pre-wrap">
+          <code>{stack}</code>
+        </pre>
+      )}
+    </div>
+  )
+}
+
 const DashboardContentUpdateLayout = ({ loaderData }: Route.ComponentProps) => {
   const { newsData } = loaderData || {}
   return <FormContentsPage newsData={newsData} />