实现业务附件受控入库 V1（05-28-business-attachment-governance-v1）

client/src/api/purchaseRequests.ts

@@ -1,4 +1,5 @@
 import { apiRequestData } from "./http";
+import type { AttachmentGovernanceFields } from "../lib/attachmentGovernance";
 import type { PrecheckResponse, RiskFlag } from "./feeControl";
 
 export type PurchaseRequestStatus = "draft" | "reviewing" | "approved" | "rejected" | "cancelled";
@@ -89,6 +90,8 @@ export type PurchaseAttachment = {
   originalName: string;
   mimeType: string;
   fileSize: number;
+  fileSha256: string | null;
+} & AttachmentGovernanceFields & {
   uploadedBy: string;
   createdAt: string | null;
   uploader: {
@@ -383,12 +386,12 @@ export async function deletePurchaseAttachment(purchaseRequestId: string, attach
   );
 }
 
-export async function issuePurchaseAttachmentSignedUrl(purchaseRequestId: string, attachmentId: string) {
+export async function issuePurchaseAttachmentSignedUrl(purchaseRequestId: string, attachmentId: string, reason?: string) {
   return apiRequestData<{ signedUrl: string; expiresAt: string }>(
     `/api/purchase-requests/${purchaseRequestId}/attachments/${attachmentId}/signed-url`,
     {
       method: "POST",
-      body: JSON.stringify({}),
+      body: JSON.stringify(reason ? { reason } : {}),
     },
   );
 }