style: 统一项目内字体单位为rem并调整布局尺寸

将项目中所有硬编码的px字体尺寸、容器宽度高度统一替换为rem单位，统一整体UI样式的尺寸规范，同时调整部分布局容器的最大宽度适配新的单位体系

src/Drama/components/DramaDetail.tsx

@@ -181,7 +181,7 @@ export function DramaDetail({ dramaId }: DramaDetailPageProps) {
             </Panel>
 
             {drama && (
-                <Modal title="编辑短剧" visible={editVisible} onCancel={() => setEditVisible(false)} footer={null} style={{ width: 720 }}>
+                <Modal title="编辑短剧" visible={editVisible} onCancel={() => setEditVisible(false)} footer={null} style={{ width: "45rem" }}>
                     <Form
                         key={drama.id}
                         layout="vertical"

src/Drama/components/DramaList.tsx

@@ -164,7 +164,7 @@ export function DramaList() {
                 />
             </Panel>
 
-            <Modal title="创建短剧" visible={visible} onCancel={() => setVisible(false)} footer={null} style={{ width: 640 }}>
+            <Modal title="创建短剧" visible={visible} onCancel={() => setVisible(false)} footer={null} style={{ width: "40rem" }}>
                 <Form layout="vertical" onSubmit={createDrama} initialValues={{ status: "draft", isRecommended: false, sortOrder: 0, totalEpisodes: 1, channelId: defaultChannel?.id }}>
                     <Form.Item label="标题" field="title" rules={[{ required: true }]}>
                         <Input placeholder="请输入短剧标题" />

src/Drama/components/EpisodeTable.tsx

@@ -117,7 +117,7 @@ export function EpisodeTable({ episodes, loading, uploadingEpisodeId, onUploadVi
             />
 
             {editingEpisode && (
-                <Modal title={`编辑第 ${editingEpisode.episodeNo} 集`} visible={Boolean(editingEpisode)} onCancel={() => setEditingEpisode(null)} footer={null} style={{ width: 680 }}>
+                <Modal title={`编辑第 ${editingEpisode.episodeNo} 集`} visible={Boolean(editingEpisode)} onCancel={() => setEditingEpisode(null)} footer={null} style={{ width: "42.5rem" }}>
                     <Form
                         key={editingEpisode.id}
                         layout="vertical"