refactor: 优化后台文章大纲组件及编辑页侧边栏布局

src/lib/components/admin/ArticleOutline.svelte

@@ -6,7 +6,6 @@
 
 <nav aria-label="正文大纲" class="article-outline">
 	{#if outline.headings.length}
-		<p class="count">{outline.headings.length} 个标题</p>
 		<ul>
 			{#each outline.headings as heading, index (heading.from)}
 				<li>

src/lib/components/admin/OutlinePopover.svelte

@@ -97,7 +97,7 @@
 		background: transparent;
 		border: 0;
 		cursor: pointer;
-		border-radius: 4px;
+		/* border-radius removed */
 	}
 	.trigger {
 		display: flex;

src/routes/admin/posts/[id]/+page.svelte

@@ -370,6 +370,8 @@
 		flex-direction: column;
 		gap: 16px;
 		z-index: 10;
+		max-height: calc(100vh - 40px);
+		overflow-y: auto;
 	}
 
 	.sidebar-panel {
@@ -392,6 +394,8 @@
 			flex-direction: column;
 			gap: 16px;
 			margin-top: 20px;
+			max-height: none;
+			overflow-y: visible;
 		}
 	}
 

src/routes/admin/posts/new/+page.svelte

@@ -400,6 +400,8 @@
 		flex-direction: column;
 		gap: 16px;
 		z-index: 10;
+		max-height: calc(100vh - 40px);
+		overflow-y: auto;
 	}
 
 	.sidebar-panel {
@@ -422,6 +424,8 @@
 			flex-direction: column;
 			gap: 16px;
 			margin-top: 20px;
+			max-height: none;
+			overflow-y: visible;
 		}
 	}