Sync kit docs (#1424)

sync kit docs

Co-authored-by: svelte-docs-bot[bot] <196124396+svelte-docs-bot[bot]@users.noreply.github.com>

Author: github-actions[bot]

apps/svelte.dev/content/docs/kit/98-reference/10-@sveltejs-kit.md

@@ -150,7 +150,7 @@ Checks whether this is an error thrown by `error`.
 ```dts
 function isHttpError<T extends number>(
 	e: unknown,
-	status?: T
+	status?: T | undefined
 ): e is HttpError_1 & {
 	status: T extends undefined ? never : T;
 };
@@ -181,7 +181,10 @@ Create a JSON `Response` object from the supplied data.
 <div class="ts-block">
 
 ```dts
-function json(data: any, init?: ResponseInit): Response;
+function json(
+	data: any,
+	init?: ResponseInit | undefined
+): Response;
 ```
 
 </div>
@@ -264,7 +267,10 @@ Create a `Response` object from the supplied body.
 <div class="ts-block">
 
 ```dts
-function text(body: string, init?: ResponseInit): Response;
+function text(
+	body: string,
+	init?: ResponseInit | undefined
+): Response;
 ```
 
 </div>
@@ -2472,7 +2478,7 @@ A map of environment variables.
 <div class="ts-block-property">
 
 ```dts
-read?: (file: string) => ReadableStream;
+read?: (file: string) => MaybePromise<ReadableStream | null>;
 ```
 
 <div class="ts-block-property-details">

apps/svelte.dev/content/docs/kit/98-reference/20-$app-navigation.md

@@ -95,16 +95,18 @@ For external URLs, use `window.location = url` instead of calling `goto(url)`.
 ```dts
 function goto(
 	url: string | URL,
-	opts?: {
-		replaceState?: boolean | undefined;
-		noScroll?: boolean | undefined;
-		keepFocus?: boolean | undefined;
-		invalidateAll?: boolean | undefined;
-		invalidate?:
-			| (string | URL | ((url: URL) => boolean))[]
-			| undefined;
-		state?: App.PageState | undefined;
-	}
+	opts?:
+		| {
+				replaceState?: boolean | undefined;
+				noScroll?: boolean | undefined;
+				keepFocus?: boolean | undefined;
+				invalidateAll?: boolean | undefined;
+				invalidate?:
+					| (string | URL | ((url: URL) => boolean))[]
+					| undefined;
+				state?: App.PageState | undefined;
+		  }
+		| undefined
 ): Promise<void>;
 ```