feat(ux): 交互元素悬浮/聚焦/按压状态增强

表格行悬浮高亮、StyleSelector 药丸按钮键盘焦点环。

frontend/src/components/StyleSelector.module.css

@@ -50,6 +50,11 @@
   color: #fff;
 }
 
+.pill:focus-visible {
+  outline: 2px solid var(--accent);
+  outline-offset: 2px;
+}
+
 /* compact 模式 */
 .compact .category {
   flex-direction: row;

frontend/src/pages/ProjectPage.tsx

@@ -112,7 +112,7 @@ export default function ProjectPage() {
               {tasks.map(task => {
                 const statusInfo = STATUS_LABELS[task.status] ?? STATUS_LABELS.pending
                 return (
-                  <tr key={task.id} style={{ borderBottom: '1px solid var(--border)' }}>
+                  <tr key={task.id} className="table-row-hover" style={{ borderBottom: '1px solid var(--border)' }}>
                     <td style={tdStyle}>{task.prompt}</td>
                     <td style={tdStyle}>{task.assetType}</td>
                     <td style={{ ...tdStyle, color: statusInfo.color }}>{statusInfo.label}</td>