Enhance UI/UX for book info and discover pages

Book Info Page Improvements:
- Add quick stats row (chapters, rating, readers)
- Enhance author display with better typography
- Improve genre tags with amber-branded pills
- Add green badge for 'ongoing' status
- Wrap summary in card with better styling
- Enhance 'More' button with proper design
- Improve StarRating component to show rating more prominently

Discover Page Improvements:
- Add progress bar showing completion through deck
- Enhance keyboard shortcuts with visual kbd elements
- Improve empty state with better visuals and CTA hierarchy
- Enhance toast notifications with icons and color-coded backgrounds
- Add auto-dismiss for toast (4s timeout)
- Improve preferences modal button labels
- Add undo functionality for last vote
- Better stat display (X of Y remaining)

All changes maintain consistency with LibNovel's design system.

ui/src/lib/components/StarRating.svelte

@@ -16,7 +16,7 @@
 	const display = $derived(hovered || rating || 0);
 </script>
 
-<div class="flex items-center gap-1">
+<div class="flex items-center gap-2">
 	<div class="flex items-center gap-0.5">
 		{#each [1,2,3,4,5] as star}
 			<button
@@ -44,10 +44,13 @@
 			</button>
 		{/each}
 	</div>
-	{#if avg && count}
-		<span class="text-xs text-(--color-muted) ml-1">{avg} ({count})</span>
-	{:else if avg}
-		<span class="text-xs text-(--color-muted) ml-1">{avg}</span>
+	{#if count > 0}
+		<div class="flex flex-col">
+			<span class="text-sm font-semibold text-(--color-text)">{avg.toFixed(1)}</span>
+			<span class="text-xs text-(--color-muted) leading-none">{count} {count === 1 ? 'rating' : 'ratings'}</span>
+		</div>
+	{:else if !readonly}
+		<span class="text-xs text-(--color-muted)">Rate this book</span>
 	{/if}
 </div>