fix(reader): use proper templ expression for back link href and clean up formatting

The back link in ReaderChrome used literal curly braces inside the href
attribute string (href="/media-items/{ metadata.MediaItemID }") which
doesn't interpolate the variable in templ. Changed to use the correct
templ expression syntax: href={ "/media/" + metadata.MediaItemID }.

Also fixed minor formatting issues:
- Normalize whitespace in comment after closing div
- Collapse empty navigator-viewport div to single line

templates/reader.templ

@@ -55,7 +55,7 @@ templ ReaderChrome(user User, metadata ReaderMetadata, progress ReadingProgress)
 		<!-- Top bar -->
 		<div class="fixed top-0 left-0 right-0 bg-opacity-95 backdrop-blur border-b z-40" style="background-color: var(--bg-primary);">
 			<div class="flex items-center justify-between px-4 py-3">
-				<a href="/media-items/{ metadata.MediaItemID }" class="text-lg hover:underline">
+				<a href={ "/media/" + metadata.MediaItemID } class="text-lg hover:underline">
 					← Back
 				</a>
 				<h1 class="text-lg font-semibold">{ metadata.Title }</h1>
@@ -325,8 +325,7 @@ templ ReaderNavigatorPanel() {
 			</div>
 		</div>
 		<div class="panel-content p-2 overflow-hidden">
-			<div id="navigator-viewport" class="relative w-full h-full">
+			<div id="navigator-viewport" class="relative w-full h-full"></div>
-			</div>
 		</div>
 	</div>
 }