reading: split the book tracker into books, papers and articles (kind column + migration classifying 20 papers), segmented tabs with counts, article cards that open the link, owner + add link with server-side unfurl, kind switch on detail pages, /trackers/reading alias

src/lib/projects.ts

@@ -92,8 +92,8 @@ const allTrackers: readonly (Tracker & { private: boolean })[] = [
 		private: false
 	},
 	{
-		name: 'books',
-		subtitle: 'my library: what I am reading, have read and want to read',
+		name: 'reading',
+		subtitle: 'books, scientific papers and articles I am reading, have read and want to read',
 		href: '/trackers/books',
 		external: false,
 		private: false