fix: add missing export for a documented image service utility (#14276)

Co-authored-by: ascorbic <213306+ascorbic@users.noreply.github.com>

Author: ArmandPhilippot

.changeset/smart-squids-pick.md

@@ -0,0 +1,5 @@
+---
+'astro': patch
+---
+
+Adds a missing export for `resolveSrc`, a documented image services utility.

packages/astro/src/assets/utils/index.ts

@@ -5,7 +5,7 @@
  * If some functions don't need to be exposed, just import the file that contains the functions.
  */
 
-export { isESMImportedImage, isRemoteImage } from './imageKind.js';
+export { isESMImportedImage, isRemoteImage, resolveSrc } from './imageKind.js';
 export { imageMetadata } from './metadata.js';
 export {
 	/**