fix(astro): Export AstroSession type (#13843)

Co-authored-by: Luiz Ferraz <[email protected]>

Author: z1haze

.changeset/tidy-mails-cough.md

@@ -0,0 +1,5 @@
+---
+'astro': patch
+---
+
+Export type `AstroSession` to allow use in explicitly typed safe code.

packages/astro/src/types/public/index.ts

@@ -43,3 +43,4 @@ export type {
 	AstroCookies,
 } from '../../core/cookies/index.js';
 export type { ContainerRenderer } from '../../container/index.js';
+export { AstroSession } from '../../core/session.js';