refactor: 将 Markdown 导入按钮移至侧边栏

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

@@ -208,11 +208,8 @@
 
 <div class="admin-page-header">
 	<h2>编辑</h2>
-	<div style="display: flex; align-items: center; gap: 12px;">
-		<button type="button" class="btn btn-secondary" onclick={() => fileInput?.click()}>📁 导入 Markdown</button>
 	<a href="/admin/posts" class="btn btn-secondary">&larr; 返回</a>
 </div>
-</div>
 <input type="file" bind:this={fileInput} accept=".md,.markdown,.txt" style="display:none" onchange={handleImportMarkdown} />
 
 {#if form?.error}
@@ -379,6 +376,11 @@
 					{/if}
 				</div>
 			</div>
+
+			<div class="sidebar-box">
+				<h3>导入</h3>
+				<button type="button" class="btn btn-secondary" style="width: 100%; text-align: center;" onclick={() => fileInput?.click()}>导入 Markdown</button>
+			</div>
 		</div>
 	</div>
 </form>

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

@@ -214,11 +214,8 @@
 
 <div class="admin-page-header">
 	<h2>新{$page.data.aliases?.post || '文章'}</h2>
-	<div style="display: flex; align-items: center; gap: 12px;">
-		<button type="button" class="btn btn-secondary" onclick={() => fileInput?.click()}>📁 导入 Markdown</button>
 	<a href="/admin/posts" class="btn btn-secondary">&larr; 返回</a>
 </div>
-</div>
 <input type="file" bind:this={fileInput} accept=".md,.markdown,.txt" style="display:none" onchange={handleImportMarkdown} />
 
 {#if form?.error}
@@ -385,6 +382,11 @@
 					{/if}
 				</div>
 			</div>
+
+			<div class="sidebar-box">
+				<h3>导入</h3>
+				<button type="button" class="btn btn-secondary" style="width: 100%; text-align: center;" onclick={() => fileInput?.click()}>导入 Markdown</button>
+			</div>
 		</div>
 	</div>
 </form>