feat: 多页面UI打磨 — 设置面板、状态反馈与样式升级

本次更新对多个功能页面进行了系统性的 UI/UX 打磨，统一了交互模式并补充了缺失的状态反馈。

## 新增功能
- WorkbenchPage: 图片提示词案例区域新增加载骨架屏、错误回退、空数据三种状态展示
- CharacterMixPage: 新增左侧设置面板（驱动提示词、图像检测开关、水印开关），支持清除已上传的人物图/参考视频
- DigitalHumanPage: 新增左侧设置面板（提示词输入、去水印/保留原声开关），支持清除已上传的人像/音频，增加取消生成按钮
- ImageWorkbenchPage / ResolutionUpscalePage: 新增参数设置面板和资产清除交互
- MorePage: 新增页面入口

## UI 优化
- 统一 Toggle 开关组件: 所有设置页面采用一致的 .studio-toggle 交互模式
- 资产清除: 各上传区域新增清除按钮，含二次确认和提示反馈
- 生成按钮: 统一为带图标的 .studio-generate-btn，增加 disabled/loading 状态
- ConversationSidebar / ProjectSidebar: 侧边栏交互细节优化

## 样式升级
- image-workbench.css: 大幅扩展样式 (+1900 行)，覆盖设置面板、上传区、结果展示等
- workbench.css: 新增 666 行样式，含骨架屏动画、案例卡片网格、状态占位等
- subtitle-removal.css: 补充设置面板样式

src/features/image-workbench/ImageWorkbenchPage.tsx

@@ -609,6 +609,20 @@ function ImageWorkbenchPage({ initialTool = "workbench", onOpenMore, onSelectVie
     </div>
   );
 
+  const handleRemoveWorkbenchResult = (index: number) => {
+    setResultImages((current) => {
+      const next = current.filter((_, imageIndex) => imageIndex !== index);
+      if (next.length) {
+        saveToolTaskState("imagewb", { taskId: taskIdRef.current || "", resultUrl: next[0], status: "完成", progress: 100 });
+        setStatus(`已移除生成图，剩余 ${next.length} 张`);
+      } else {
+        clearToolTaskState("imagewb");
+        setStatus("已移除生成图");
+      }
+      return next;
+    });
+  };
+
   const handleGenerate = async () => {
     if (!referenceImages.length && !prompt.trim()) {
       setStatus("请先上传参考图或输入提示词");
@@ -797,7 +811,7 @@ function ImageWorkbenchPage({ initialTool = "workbench", onOpenMore, onSelectVie
                     aria-label="删除局部重绘素材"
                     onClick={handleRemoveInpaintImage}
                   >
-                    ×
+                    <DeleteOutlined />
                   </button>
                 ) : null}
               </div>
@@ -830,7 +844,7 @@ function ImageWorkbenchPage({ initialTool = "workbench", onOpenMore, onSelectVie
               </label>
             </section>
 
-            <section className="image-workbench-control-card">
+            <section className="image-workbench-control-card image-workbench-inpaint-params-card">
               <h3>参数</h3>
               <span className="image-workbench-field-label">输出分辨率</span>
               <div className="image-workbench-segmented">
@@ -842,7 +856,7 @@ function ImageWorkbenchPage({ initialTool = "workbench", onOpenMore, onSelectVie
               </div>
             </section>
 
-            <section className="image-workbench-control-card">
+            <section className="image-workbench-control-card image-workbench-inpaint-prompt-card">
               <h3>提示词</h3>
               <textarea
                 className="image-workbench-prompt"
@@ -967,7 +981,7 @@ function ImageWorkbenchPage({ initialTool = "workbench", onOpenMore, onSelectVie
       ) : activeTool === "camera" ? (
         <main className="image-workbench-layout image-workbench-layout--camera">
           <aside className="image-workbench-panel image-workbench-panel--left">
-            <section className="image-workbench-control-card">
+            <section className="image-workbench-control-card image-workbench-camera-material">
               <div className="image-workbench-section-title">
                 <h3>素材</h3>
                 <span>{cameraImage ? "已导入" : "待上传"}</span>
@@ -997,7 +1011,7 @@ function ImageWorkbenchPage({ initialTool = "workbench", onOpenMore, onSelectVie
                     aria-label="删除镜头参考图"
                     onClick={handleRemoveCameraImage}
                   >
-                    ×
+                    <DeleteOutlined />
                   </button>
                 ) : null}
               </div>
@@ -1248,7 +1262,7 @@ function ImageWorkbenchPage({ initialTool = "workbench", onOpenMore, onSelectVie
                       aria-label={`删除参考图 ${index + 1}`}
                       onClick={() => handleRemoveReferenceImage(index)}
                     >
-                      ×
+                      <DeleteOutlined />
                     </button>
                   </div>
                 ))}
@@ -1282,7 +1296,7 @@ function ImageWorkbenchPage({ initialTool = "workbench", onOpenMore, onSelectVie
                     aria-label="删除参考图"
                     onClick={() => handleRemoveReferenceImage(0)}
                   >
-                    ×
+                    <DeleteOutlined />
                   </button>
                 ) : null}
               </div>
@@ -1300,7 +1314,7 @@ function ImageWorkbenchPage({ initialTool = "workbench", onOpenMore, onSelectVie
             </div>
           </section>
 
-          <section className="image-workbench-control-card">
+          <section className="image-workbench-control-card image-workbench-output-card">
             <h3>输出</h3>
             <span className="image-workbench-field-label">尺寸</span>
             <div className="image-workbench-segmented">
@@ -1365,6 +1379,14 @@ function ImageWorkbenchPage({ initialTool = "workbench", onOpenMore, onSelectVie
             <div className="image-workbench-result-grid">
               {resultImages.map((url, i) => (
                 <div key={url} className="image-workbench-result-card">
+                  <button
+                    type="button"
+                    className="image-workbench-result-remove"
+                    aria-label={`移除生成结果 ${i + 1}`}
+                    onClick={() => handleRemoveWorkbenchResult(i)}
+                  >
+                    <DeleteOutlined />
+                  </button>
                   <a href={url} target="_blank" rel="noopener noreferrer" className="image-workbench-result-item">
                     <img src={url} alt={`生成结果 ${i + 1}`} />
                   </a>