fix: chapter list modal full-screen clip + add clear close button

Root cause: the chapter picker overlay (fixed inset-0) was rendered as a
descendant of the AudioPlayer's wrapping div, which is itself inside a
'rounded-b-lg overflow-hidden' container on the chapter page. Chrome clips
position:fixed descendants when a parent has overflow:hidden + border-radius,
so the overlay was constrained to the parent's bounding box instead of
covering the full viewport.

Fix: moved the {#if showChapterPanel} block from inside the standard player
div to a top-level sibling at the end of the component template. Svelte
components support multiple root nodes, so the overlay is now a sibling of
all player containers — no ancestor overflow-hidden can clip it.

Also replaced the subtle chevron-down close button with a clear X (×) button
in the top-right of the header, making it obvious how to dismiss the panel.

ui/src/lib/components/AudioPlayer.svelte

@@ -1166,78 +1166,7 @@
 		</div>
 	{/if}
 
-	<!-- ── Chapter picker overlay ────────────────────────────────────────── -->
+
-	{#if showChapterPanel && audioStore.chapters.length > 0}
-		<!-- svelte-ignore a11y_no_static_element_interactions -->
-		<div
-			class="fixed inset-0 z-[60] flex flex-col"
-			style="background: var(--color-surface);"
-		>
-			<!-- Header -->
-			<div class="flex items-center gap-3 px-4 py-3 border-b border-(--color-border) shrink-0">
-				<button
-					type="button"
-					onclick={() => { showChapterPanel = false; chapterSearch = ''; }}
-					class="p-2 rounded-full text-(--color-muted) hover:text-(--color-text) hover:bg-(--color-surface-2) transition-colors"
-					aria-label="Close chapter picker"
-				>
-					<svg class="w-5 h-5" fill="none" stroke="currentColor" viewBox="0 0 24 24">
-						<path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M19 9l-7 7-7-7"/>
-					</svg>
-				</button>
-				<span class="text-xs font-semibold text-(--color-muted) uppercase tracking-wider flex-1">Chapters</span>
-			</div>
-			<!-- Search -->
-			<div class="px-4 py-3 shrink-0 border-b border-(--color-border)">
-				<div class="relative">
-					<svg class="absolute left-3 top-1/2 -translate-y-1/2 w-4 h-4 text-(--color-muted)" fill="none" stroke="currentColor" viewBox="0 0 24 24">
-						<path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M21 21l-6-6m2-5a7 7 0 11-14 0 7 7 0 0114 0z"/>
-					</svg>
-					<input
-						type="search"
-						placeholder="Search chapters…"
-						bind:value={chapterSearch}
-						class="w-full pl-9 pr-4 py-2 text-sm bg-(--color-surface-2) border border-(--color-border) rounded-lg text-(--color-text) placeholder:text-(--color-muted) focus:outline-none focus:border-(--color-brand) transition-colors"
-					/>
-				</div>
-			</div>
-			<!-- Chapter list -->
-			<div class="flex-1 overflow-y-auto">
-				{#each filteredChapters as ch (ch.number)}
-					<button
-						type="button"
-						onclick={() => playChapter(ch.number)}
-						class={cn(
-							'w-full flex items-center gap-3 px-4 py-3 border-b border-(--color-border)/40 transition-colors text-left',
-							ch.number === chapter ? 'bg-(--color-brand)/8' : 'hover:bg-(--color-surface-2)'
-						)}
-					>
-						<!-- Chapter number badge (mirrors voice radio indicator) -->
-						<span class={cn(
-							'w-8 h-8 shrink-0 rounded-full border-2 flex items-center justify-center tabular-nums text-xs font-semibold transition-colors',
-							ch.number === chapter
-								? 'border-(--color-brand) bg-(--color-brand) text-(--color-surface)'
-								: 'border-(--color-border) text-(--color-muted)'
-						)}>{ch.number}</span>
-						<!-- Title -->
-						<span class={cn(
-							'flex-1 text-sm truncate',
-							ch.number === chapter ? 'font-semibold text-(--color-brand)' : 'text-(--color-text)'
-						)}>{ch.title || `Chapter ${ch.number}`}</span>
-						<!-- Now-playing indicator -->
-						{#if ch.number === chapter}
-							<svg class="w-4 h-4 shrink-0 text-(--color-brand)" fill="currentColor" viewBox="0 0 24 24">
-								<path d="M8 5v14l11-7z"/>
-							</svg>
-						{/if}
-					</button>
-				{/each}
-				{#if filteredChapters.length === 0}
-					<p class="px-4 py-8 text-sm text-(--color-muted) text-center">No chapters match "{chapterSearch}"</p>
-				{/if}
-			</div>
-		</div>
-	{/if}
 
 	{#if audioStore.isCurrentChapter(slug, chapter)}
 		<!-- ── This chapter is the active one ── -->
@@ -1318,3 +1247,79 @@
 	{/if}
 </div>
 {/if}
+
+<!-- ── Chapter picker overlay ─────────────────────────────────────────────────
+     Rendered as a top-level sibling (outside all player containers) so that
+     the fixed inset-0 positioning is never clipped by overflow-hidden or
+     border-radius on any ancestor wrapping the AudioPlayer component.        -->
+{#if showChapterPanel && audioStore.chapters.length > 0}
+	<!-- svelte-ignore a11y_no_static_element_interactions -->
+	<div
+		class="fixed inset-0 z-[60] flex flex-col"
+		style="background: var(--color-surface);"
+	>
+		<!-- Header -->
+		<div class="flex items-center gap-3 px-4 py-3 border-b border-(--color-border) shrink-0">
+			<span class="text-sm font-semibold text-(--color-text) flex-1">Chapters</span>
+			<button
+				type="button"
+				onclick={() => { showChapterPanel = false; chapterSearch = ''; }}
+				class="w-9 h-9 flex items-center justify-center rounded-full text-(--color-muted) hover:text-(--color-text) hover:bg-(--color-surface-2) transition-colors"
+				aria-label="Close chapter picker"
+			>
+				<svg class="w-5 h-5" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+					<path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M6 18L18 6M6 6l12 12"/>
+				</svg>
+			</button>
+		</div>
+		<!-- Search -->
+		<div class="px-4 py-3 shrink-0 border-b border-(--color-border)">
+			<div class="relative">
+				<svg class="absolute left-3 top-1/2 -translate-y-1/2 w-4 h-4 text-(--color-muted)" fill="none" stroke="currentColor" viewBox="0 0 24 24">
+					<path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M21 21l-6-6m2-5a7 7 0 11-14 0 7 7 0 0114 0z"/>
+				</svg>
+				<input
+					type="search"
+					placeholder="Search chapters…"
+					bind:value={chapterSearch}
+					class="w-full pl-9 pr-4 py-2 text-sm bg-(--color-surface-2) border border-(--color-border) rounded-lg text-(--color-text) placeholder:text-(--color-muted) focus:outline-none focus:border-(--color-brand) transition-colors"
+				/>
+			</div>
+		</div>
+		<!-- Chapter list -->
+		<div class="flex-1 overflow-y-auto">
+			{#each filteredChapters as ch (ch.number)}
+				<button
+					type="button"
+					onclick={() => playChapter(ch.number)}
+					class={cn(
+						'w-full flex items-center gap-3 px-4 py-3 border-b border-(--color-border)/40 transition-colors text-left',
+						ch.number === chapter ? 'bg-(--color-brand)/8' : 'hover:bg-(--color-surface-2)'
+					)}
+				>
+					<!-- Chapter number badge -->
+					<span class={cn(
+						'w-8 h-8 shrink-0 rounded-full border-2 flex items-center justify-center tabular-nums text-xs font-semibold transition-colors',
+						ch.number === chapter
+							? 'border-(--color-brand) bg-(--color-brand) text-(--color-surface)'
+							: 'border-(--color-border) text-(--color-muted)'
+					)}>{ch.number}</span>
+					<!-- Title -->
+					<span class={cn(
+						'flex-1 text-sm truncate',
+						ch.number === chapter ? 'font-semibold text-(--color-brand)' : 'text-(--color-text)'
+					)}>{ch.title || `Chapter ${ch.number}`}</span>
+					<!-- Now-playing indicator -->
+					{#if ch.number === chapter}
+						<svg class="w-4 h-4 shrink-0 text-(--color-brand)" fill="currentColor" viewBox="0 0 24 24">
+							<path d="M8 5v14l11-7z"/>
+						</svg>
+					{/if}
+				</button>
+			{/each}
+			{#if filteredChapters.length === 0}
+				<p class="px-4 py-8 text-sm text-(--color-muted) text-center">No chapters match "{chapterSearch}"</p>
+			{/if}
+		</div>
+	</div>
+{/if}