Sync kit docs (#1385)

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/30-advanced/20-hooks.md

@@ -321,7 +321,7 @@ export async function reroute({ url, fetch }) {
 
 ### transport
 
-This is a collection of _transporters_, which allow you to pass custom types — returned from `load` and form actions — across the server/client boundary. Each transporter contains an `encode` function, which encodes values on the server (or returns `false` for anything that isn't an instance of the type) and a corresponding `decode` function:
+This is a collection of _transporters_, which allow you to pass custom types — returned from `load` and form actions — across the server/client boundary. Each transporter contains an `encode` function, which encodes values on the server (or returns a falsy value for anything that isn't an instance of the type) and a corresponding `decode` function:
 
 ```js
 /// file: src/hooks.js