Revert "[verified] feat: add external calendar subscriptions"

This reverts commit 583b6a8a9d.

backend/backup/archive.py

@@ -152,18 +152,6 @@ def parse_archive_path(path: Path, *, max_archive_bytes: int = MAX_ARCHIVE_BYTES
             content_names = set(names) - {"manifest.json"}
             if set(checksums) != content_names:
                 raise backup_error("backup_manifest_mismatch", "manifest 与 ZIP 条目不一致")
-            # Calendar subscriptions are an additive backup-v2 entity. Accept archives
-            # produced by older helpers that checksum the new file but omit its count.
-            optional_entities = {"calendar_subscriptions"}
-            undeclared_optional = {
-                f"data/{name}.json" for name in optional_entities - set(declared_entities)
-            }
-            if set(declared_entities) != {
-                name[5:-5]
-                for name in content_names - undeclared_optional
-                if name.startswith("data/") and name.endswith(".json")
-            }:
-                raise backup_error("backup_manifest_mismatch", "manifest 实体清单不一致")
             entities: dict[str, list[dict]] = {}
             files: dict[str, StagedBlob] = {}
             for index, name in enumerate(sorted(content_names)):
@@ -182,11 +170,7 @@ def parse_archive_path(path: Path, *, max_archive_bytes: int = MAX_ARCHIVE_BYTES
                 if not isinstance(checksums[name], str) or actual_digest != checksums[name]:
                     raise backup_error("backup_checksum_mismatch", "备份校验和不匹配")
             if set(declared_entities) != set(entities):
-                required_declared = set(entities) - optional_entities
-                if set(declared_entities) != required_declared or any(
-                    entities.get(name) for name in optional_entities - set(declared_entities)
-                ):
-                    raise backup_error("backup_manifest_mismatch", "manifest 实体清单不一致")
+                raise backup_error("backup_manifest_mismatch", "manifest 实体清单不一致")
             if any(type(count) is not int or count < 0 or count != len(entities[name]) for name, count in declared_entities.items()):
                 raise backup_error("backup_manifest_mismatch", "manifest 实体数量不一致")
     except HTTPException: