feat: add JSON-LD structured data (#260)

- Add author profile to SITE variables
- Add JSON-LD to Layout.astro

src/types.ts

@@ -3,6 +3,7 @@ import type socialIcons from "@assets/socialIcons";
 export type Site = {
   website: string;
   author: string;
+  profile: string;
   desc: string;
   title: string;
   ogImage?: string;