收口前端平台组件库能力

新增 PlatformUiKit 通用弹窗、按钮、状态、空态、媒体、表单和标签等公共组件
迁移结果页、创作工作台、认证入口、RPG 暗色面板和运行态弹窗的重复 UI chrome
补充组件测试、页面回归测试、技术文档和 Hermes 共享决策记录

src/components/common/PlatformPillSwitch.tsx

@@ -0,0 +1,56 @@
+import type { InputHTMLAttributes, ReactNode } from 'react';
+
+type PlatformPillSwitchProps = Omit<
+  InputHTMLAttributes<HTMLInputElement>,
+  'children' | 'type'
+> & {
+  label: ReactNode;
+};
+
+/**
+ * 平台胶囊开关。
+ * 统一承载图片面板中类似 AI 重绘的 label + switch 语义和视觉。
+ */
+export function PlatformPillSwitch({
+  label,
+  checked,
+  disabled,
+  className,
+  ...inputProps
+}: PlatformPillSwitchProps) {
+  return (
+    <label
+      className={[
+        'inline-flex cursor-pointer items-center gap-2 rounded-full border border-white/80 bg-white/94 px-3 py-2 text-xs font-black text-[var(--platform-text-strong)] shadow-sm backdrop-blur',
+        disabled ? 'cursor-not-allowed opacity-55' : null,
+        className,
+      ]
+        .filter(Boolean)
+        .join(' ')}
+    >
+      <span>{label}</span>
+      <input
+        {...inputProps}
+        role="switch"
+        type="checkbox"
+        checked={checked}
+        disabled={disabled}
+        className="sr-only"
+      />
+      <span
+        aria-hidden="true"
+        className={[
+          'relative h-5 w-9 rounded-full transition',
+          checked ? 'bg-[var(--platform-accent)]' : 'bg-zinc-300',
+        ].join(' ')}
+      >
+        <span
+          className={[
+            'absolute top-0.5 h-4 w-4 rounded-full bg-white shadow-sm transition',
+            checked ? 'left-[1.125rem]' : 'left-0.5',
+          ].join(' ')}
+        />
+      </span>
+    </label>
+  );
+}