feat(embed-slots): soft-delete slots — admin entry, ov shutdown via enabled=false snapshot

- 契约 deleteEmbedSlot（DELETE /admin/embed-slots/{id} → 204 幂等；admin 专属）
- cn schema：embed_slots.deletedAt（迁移 20260923120000，本地已应用）
- softDelete：乐观锁 claim + outbox slot.updated（payload enabled 强制 false
  ——ov 副本无墓碑，enabled=false 快照即公开端 404 下线；priority=high）+ audit
- 列表/加载/更新过滤 deletedAt → 同码 404
- Admin 列表操作「删除」（确认：已接入网站将停止展示、不可恢复）
- API 56/56、admin 87/87 + build 全绿

Co-Authored-By: Claude Code <noreply@anthropic.com>

services/api/src/embed/embed.controller.ts

@@ -7,6 +7,8 @@
 import {
   Body,
   Controller,
+  Delete,
+  HttpCode,
   Get,
   Param,
   Patch,
@@ -14,6 +16,7 @@ import {
   Query,
   Req,
   UseGuards,
+  HttpStatus,
 } from '@nestjs/common';
 import { userOf } from '../albums/albums.controller';
 import { AuthenticatedRequest, SessionGuard } from '../auth/session.guard';
@@ -53,6 +56,15 @@ export class EmbedSlotsController {
   }
 
   /** 部分更新（任一管理面变更递增 configVersion 并触发 slot-state 同步）。 */
+  @Delete(':id')
+  @HttpCode(HttpStatus.NO_CONTENT)
+  deleteEmbedSlot(
+    @Param('id') id: string,
+    @Req() req: AuthenticatedRequest,
+  ): Promise<void> {
+    return this.embedSlotsService.softDelete(userOf(req), id);
+  }
+
   @Patch(':id')
   updateEmbedSlot(
     @Param('id') id: string,

services/api/src/embed/embed.service.ts

@@ -193,7 +193,10 @@ export class EmbedSlotsService {
       }
     }
     const rows = await this.prisma.embed_slots.findMany({
-      where: decoded === null ? {} : keysetWhereDesc('createdAt', 'id', decoded),
+      where: {
+        deletedAt: null,
+        ...(decoded === null ? {} : keysetWhereDesc('createdAt', 'id', decoded)),
+      },
       orderBy: [{ createdAt: 'desc' }, { id: 'desc' }],
       take: limit + 1, // 多取一条探测 hasMore（避免额外 count）
     });
@@ -298,7 +301,7 @@ export class EmbedSlotsService {
     for (let attempt = 0; attempt < 3 && outcome === 'retry'; attempt++) {
       outcome = await this.prisma.$transaction(async (tx) => {
         const slot = await tx.embed_slots.findUnique({ where: { id: slotId } });
-        if (slot === null) {
+        if (slot === null || slot.deletedAt !== null) {
           throw slotNotFound();
         }
 
@@ -379,11 +382,72 @@ export class EmbedSlotsService {
   }
 
   /** 组装 EmbedSlot 响应（albumTitle 按绑定相册 defaultLocale 解析）。 */
+  /**
+   * 软删除（契约 deleteEmbedSlot）：deletedAt 标记 + entityVersion 自增 +
+   * outbox slot.updated（enabled=false 快照 → ov 公开端 404 下线）+ audit。
+   * 管理列表隐藏；数据保留，无恢复端点。幂等：重复删除 204。
+   */
+  async softDelete(user: AuthUser, slotId: string): Promise<void> {
+    this.assertAdmin(user);
+    for (let attempt = 0; attempt < 3; attempt++) {
+      const done = await this.prisma.$transaction(async (tx) => {
+        const slot = await tx.embed_slots.findUnique({ where: { id: slotId } });
+        if (slot === null) {
+          throw slotNotFound();
+        }
+        if (slot.deletedAt !== null) {
+          return true as const; // 幂等
+        }
+        const claimed = await tx.embed_slots.updateMany({
+          where: { id: slotId, entityVersion: slot.entityVersion },
+          data: {
+            deletedAt: new Date(),
+            entityVersion: { increment: 1 },
+          },
+        });
+        if (claimed.count === 0) {
+          return false as const;
+        }
+        const updated = await tx.embed_slots.findUniqueOrThrow({
+          where: { id: slotId },
+        });
+        await tx.outbox_events.create({
+          data: {
+            type: 'slot.updated',
+            albumId: updated.albumId ?? '',
+            entityVersion: updated.entityVersion,
+            // 公开可见性下线 → high（嵌入端尽快 404）
+            priority: 'high',
+            payload: buildSlotUpdatedPayload(
+              updated,
+              null,
+            ) as unknown as Prisma.InputJsonValue,
+          },
+        });
+        await tx.audit_logs.create({
+          data: {
+            actorId: user.id,
+            action: 'embed_slot.delete',
+            resourceId: slotId,
+          },
+        });
+        return true as const;
+      });
+      if (done) return;
+    }
+    throw new ApiException(
+      ErrorCodes.INTERNAL_ERROR,
+      'Internal server error',
+      HttpStatus.INTERNAL_SERVER_ERROR,
+    );
+  }
+
   private async loadSlot(slotId: string): Promise<EmbedSlotResponse> {
     const slot = await this.prisma.embed_slots.findUnique({
       where: { id: slotId },
     });
-    if (slot === null) {
+    if (slot === null || slot.deletedAt !== null) {
+      // 已删除与不存在同码 404（软删除语义，deleteEmbedSlot）。
       throw slotNotFound();
     }
     const title = slot.albumId === null

services/api/src/sync/payloads.ts

@@ -62,6 +62,7 @@ type EmbedSlotRow = Pick<
   | 'configVersion'
   | 'settings'
   | 'entityVersion'
+  | 'deletedAt'
 >;
 
 /**
@@ -157,7 +158,9 @@ export function buildSlotUpdatedPayload(
   return {
     slotId: slot.id,
     publicToken: slot.publicToken,
-    enabled: slot.enabled,
+    // 软删除（deleteEmbedSlot）行以 enabled=false 快照下线 ov 副本
+    // （embed_slots_ov 无墓碑，enabled=false 即公开端 404）。
+    enabled: slot.deletedAt !== null ? false : slot.enabled,
     albumId: slot.albumId,
     albumPublicToken,
     configVersion: slot.configVersion,