Use absolute URLs in Atom feed

models/article.ts

@@ -1,6 +1,7 @@
+import { render as renderMarkdown } from "@deno/gfm";
 import { nip19 } from "@nostr/tools";
 import { NEvent } from "../nostr.ts";
-import { render as renderMarkdown } from "@deno/gfm";
+import config from "../config.ts";
 
 export default class Article {
   event: NEvent;
@@ -14,6 +15,10 @@ export default class Article {
     return tag ? tag[1] : "";
   }
 
+  get url(): string {
+    return `${config.base_url}/${this.naddr}`
+  }
+
   get title(): string {
     const tag = this.event.tags.find((t) => t[0] === "title");
     return tag ? tag[1] : "Untitled";