完善分发与收集任务全流程

- RestJobEx 对齐 task_id，path_file 提交目录路径
- 运行页进度仅跟接口轮询，失败态停留 page3 UI
- 完成态卡位续做，USB/任务轮询生命周期优化
- 拆分 DLL 加载、任务 staging 与提交前校验
- 移除 mock 与冗余样式，补充 native 依赖

Co-authored-by: Cursor <cursoragent@cursor.com>

app/src/main/services/dll-loader.ts

@@ -0,0 +1,20 @@
+import { setupNativeWorkingDir } from './native-path'
+
+type DllModule = typeof import('./work-dll.service')
+
+let dllMod: DllModule | null = null
+let nativeReady = false
+
+function ensureNativeEnv(): void {
+  if (nativeReady) return
+  setupNativeWorkingDir()
+  nativeReady = true
+}
+
+export async function loadDllModule(): Promise<DllModule> {
+  ensureNativeEnv()
+  if (!dllMod) {
+    dllMod = await import('./work-dll.service')
+  }
+  return dllMod
+}