fix: add proper typings for `$derived.call`

fixes #10330

.changeset/real-items-suffer.md

@@ -0,0 +1,5 @@
+---
+"svelte": patch
+---
+
+fix: add proper typings for `$derived.call`

packages/svelte/src/main/ambient.d.ts

@@ -77,7 +77,7 @@ declare namespace $derived {
 	 *
 	 * https://svelte-5-preview.vercel.app/docs/runes#$derived-call
 	 */
-	export function fn<T>(fn: () => T): void;
+	export function call<T>(fn: () => T): void;
 }
 
 /**

packages/svelte/types/index.d.ts

@@ -2485,7 +2485,7 @@ declare namespace $derived {
 	 *
 	 * https://svelte-5-preview.vercel.app/docs/runes#$derived-call
 	 */
-	export function fn<T>(fn: () => T): void;
+	export function call<T>(fn: () => T): void;
 }
 
 /**