fix: correct types for `ontoggle` on <details> elements (#18063)

`<details>` elements fire `ontoggle` as ToggleEvents
([source](https://developer.mozilla.org/en-US/docs/Web/API/HTMLElement/toggle_event)),
but they're currently just typed as Event.

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.changeset/great-toes-behave.md

@@ -0,0 +1,5 @@
+---
+'svelte': patch
+---
+
+fix: correct types for `ontoggle` on <details> elements

packages/svelte/elements.d.ts

@@ -952,9 +952,9 @@ export interface HTMLDetailsAttributes extends HTMLAttributes<HTMLDetailsElement
 
 	'bind:open'?: boolean | undefined | null;
 
-	'on:toggle'?: EventHandler<Event, HTMLDetailsElement> | undefined | null;
-	ontoggle?: EventHandler<Event, HTMLDetailsElement> | undefined | null;
-	ontogglecapture?: EventHandler<Event, HTMLDetailsElement> | undefined | null;
+	'on:toggle'?: ToggleEventHandler<HTMLDetailsElement> | undefined | null;
+	ontoggle?: ToggleEventHandler<HTMLDetailsElement> | undefined | null;
+	ontogglecapture?: ToggleEventHandler<HTMLDetailsElement> | undefined | null;
 }
 
 export interface HTMLDelAttributes extends HTMLAttributes<HTMLModElement> {