feat: 持久化资料包导出记录与列表摘要

apps/documents/models.py

@@ -92,3 +92,36 @@ class UploadedDocument(models.Model):
             self.STATUS_INDEXED: "已入库，可检索",
             self.STATUS_FAILED: "入库失败",
         }.get(self.status, self.status)
+
+
+class ExportedDocument(models.Model):
+    """
+    导出文件记录。
+
+    该对象属于资料包治理范围：
+    - Documents 维护导出产物与资料包关系
+    - Chat 只负责触发导出动作
+    - Audit 负责回看执行痕迹
+    """
+
+    batch = models.ForeignKey(
+        SubmissionBatch,
+        related_name="export_records",
+        on_delete=models.CASCADE,
+    )
+    conversation_id = models.CharField(max_length=64, db_index=True)
+    product_name = models.CharField(max_length=255, blank=True, db_index=True)
+    template_name = models.CharField(max_length=100, blank=True)
+    template_version = models.CharField(max_length=50, blank=True)
+    export_mode = models.CharField(max_length=32, db_index=True)
+    output_type = models.CharField(max_length=100, default="registration_word_export_report")
+    file_name = models.CharField(max_length=255)
+    relative_path = models.CharField(max_length=500)
+    download_url = models.CharField(max_length=500, blank=True)
+    created_at = models.DateTimeField(auto_now_add=True, db_index=True)
+
+    class Meta:
+        ordering = ["-created_at"]
+
+    def __str__(self) -> str:
+        return self.file_name