[fix] small ts fixes

Author: notnotsamuel

src/lib/Route.svelte.d.ts

@@ -1,8 +1,9 @@
-import type { Component } from 'svelte';
+import type { Component, Snippet } from 'svelte';
 
 export interface RouteProps {
   path?: string;
   component?: Component;
+  children?: Snippet<[{ params: Record<string, string> }]>;
 }
 
 declare const Route: Component<RouteProps>;

src/lib/Router.svelte.d.ts

@@ -1,4 +1,4 @@
-import type { Component } from 'svelte';
+import type { Component, Snippet } from 'svelte';
 
 export interface RouteInfo {
   path: string;
@@ -17,6 +17,7 @@ export type NavigationGuard = (context: {
 export interface RouterProps {
   url?: string;
   beforeEach?: NavigationGuard[];
+  children?: Snippet;
 }
 
 declare const Router: Component<RouterProps>;