Add download option and CD disc artwork to finished books; v2.0.31

- Add downloadUrl field to FinishedBook type
- Admin: paste any external URL (Drive, Dropbox, etc.) per finished book
- Public series page: replace square hero image with circular CD disc artwork
  (conic-gradient sheen, center hole, drop shadow, slight tilt)
- Stream Episodes + Download Album action buttons in the hero
- Grid cards show a gold download badge when a download URL is set

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/App.tsx

@@ -1617,7 +1617,12 @@ function FinishedBooksPage({ content }: { content: SiteContent }) {
             <div className="finished-books-grid">
               {books.map(book => (
                 <Link key={book.id} to={`/finished/${book.id}`} className="finished-book-card">
-                  {book.imageUrl && <img src={book.imageUrl} alt={book.title} className="finished-book-card-img" />}
+                  {book.imageUrl && (
+                    <div className="finished-book-card-img-wrap">
+                      <img src={book.imageUrl} alt={book.title} className="finished-book-card-img" />
+                      {book.downloadUrl && <span className="finished-book-card-dl-badge" title="Download available">⬇</span>}
+                    </div>
+                  )}
                   <div className="finished-book-card-body">
                     <p className="finished-book-card-season">Season {book.season}</p>
                     <h2 className="finished-book-card-title">{book.title}</h2>
@@ -1668,14 +1673,35 @@ function FinishedSeriesPage({ content }: { content: SiteContent }) {
           <span>{book.title}</span>
         </nav>
         <div className="finished-series-hero">
-          {book.imageUrl && <img src={book.imageUrl} alt={book.title} className="finished-series-hero-img" />}
+          {book.imageUrl && (
+            <div className="finished-series-cd" aria-hidden="true">
+              <div className="finished-series-cd-disc">
+                <img src={book.imageUrl} alt={book.title} className="finished-series-cd-img" />
+                <div className="finished-series-cd-sheen" />
+                <div className="finished-series-cd-hole" />
+              </div>
+            </div>
+          )}
           <div>
             <p className="finished-book-card-season">Season {book.season}</p>
             <h1 className="finished-series-title">{book.title}</h1>
             {book.description && <p className="finished-series-desc">{book.description}</p>}
+            <div className="finished-series-actions">
+              <a href="#playlist" className="finished-series-btn-stream">▶ Stream Episodes</a>
+              {book.downloadUrl && (
+                <a
+                  href={book.downloadUrl}
+                  target="_blank"
+                  rel="noopener noreferrer"
+                  className="finished-series-btn-download"
+                >
+                  ⬇ Download Album
+                </a>
+              )}
+            </div>
           </div>
         </div>
-        <h2 className="finished-series-playlist-heading">Episode Playlist</h2>
+        <h2 id="playlist" className="finished-series-playlist-heading">Episode Playlist</h2>
         {loading ? (
           <p className="finished-books-empty">Loading episodes…</p>
         ) : episodes.length === 0 ? (