Add feed discovery plugin

plugins/feed-discovery/src/output/json-feed.ts

@@ -0,0 +1,22 @@
+import type { FeedDiscoveryResponse } from "../types.js";
+
+export function renderJsonFeed(response: FeedDiscoveryResponse) {
+  return JSON.stringify(
+    {
+      version: "https://jsonfeed.org/version/1.1",
+      title: `LogicSRC feed discovery: ${response.query}`,
+      home_page_url: "https://bittorrented.com/rss",
+      feed_url: `https://bittorrented.com/json-feed/discover/${encodeURIComponent(response.normalizedQuery)}.json`,
+      items: response.results.map((result) => ({
+        id: result.canonicalFeedUrl ?? result.feedUrl,
+        url: result.homepageUrl ?? result.feedUrl,
+        title: result.title,
+        summary: result.description ?? `Discovered ${result.kind} feed from ${result.provider}`,
+        date_published: result.lastPublishedAt,
+        tags: [result.kind, result.provider, ...result.tags]
+      }))
+    },
+    null,
+    2
+  );
+}