fix: 串行化凭据所有权并响应桌面请求取消

frontend/src/services/platform/coreRequest.ts

@@ -0,0 +1,39 @@
+import { hostInvoke } from './desktop'
+
+export interface RequestProgress { issued: boolean; requestId?: string }
+
+/** A reservation makes cancel-before-dispatch definitive even across IPC ordering. */
+export function coreRequest<T>(args: Record<string, unknown>, signal: AbortSignal, timeoutMs: number, progress: RequestProgress): Promise<T> {
+  return new Promise((resolve, reject) => {
+    let settled = false
+    let requestId: string | undefined
+    const cancel = () => {
+      if (requestId) void hostInvoke('core_request_cancel', { requestId }).catch(() => {})
+    }
+    const abort = () => {
+      if (settled) return
+      settled = true
+      signal.removeEventListener('abort', abort)
+      cancel()
+      reject(new DOMException('Request aborted', 'AbortError'))
+    }
+    if (signal.aborted) { abort(); return }
+    signal.addEventListener('abort', abort, { once: true })
+    void (async () => {
+      try {
+        requestId = await hostInvoke<string>('core_request_prepare', { timeoutMs })
+        progress.requestId = requestId
+        if (settled || signal.aborted) { cancel(); return }
+        progress.issued = true
+        const result = await hostInvoke<T>('core_request', { request: { ...args, requestId } })
+        if (!settled) { settled = true; resolve(result) }
+      } catch (error) {
+        if (!settled) { settled = true; reject(error) }
+      } finally {
+        signal.removeEventListener('abort', abort)
+        // Also discard a reservation if dispatch failed before Rust claimed it.
+        cancel()
+      }
+    })()
+  })
+}