@microsoft.graph.sharedChanged annotation not set on folders in delta query with deltashowsharingchanges

Description

When using the delta query API with Prefer: deltashowremovedasdeleted, deltatraversepermissiongaps, deltashowsharingchanges headers, the @microsoft.graph.sharedChanged OData annotation is only set on files, never on folders — even when folders appear in the delta response with a shared facet.

This is an API behavior issue, not SDK-specific, but we're filing here as the docs repo has issues disabled.

Steps to reproduce

1. Get a latest delta token:

   GET /drives/{drive-id}/root/delta?token=latest
   Headers: Prefer: deltashowremovedasdeleted, deltatraversepermissiongaps, deltashowsharingchanges
   

2. Share a file located inside a folder hierarchy (e.g., root/folder/sub-folder/sample.jpg) with a specific user.

3. Query delta with the token from step 1:

   GET /drives/{drive-id}/root/delta?token={token}
   Headers: Prefer: deltashowremovedasdeleted, deltatraversepermissiongaps, deltashowsharingchanges
   

Actual result

The response contains 4 items. Only the file has @microsoft.graph.sharedChanged, the parent folders do not:

FOLDER root       — @microsoft.graph.sharedChanged: NOT PRESENT
FOLDER folder     — @microsoft.graph.sharedChanged: NOT PRESENT, shared: {scope: users}
FOLDER sub-folder — @microsoft.graph.sharedChanged: NOT PRESENT
FILE   sample.jpg — @microsoft.graph.sharedChanged: true, shared: {scope: users}

Expected result

Per the documentation:

"all items that appear in the delta query response due to permission changes have the @microsoft.graph.sharedChanged: True OData annotation"

Parent folders that appear as hierarchy context (not due to their own permission change) should either:

• Have @microsoft.graph.sharedChanged set when they are directly shared, OR
• Be excluded from the response when they are only hierarchy context

Currently, folders never receive the annotation regardless of whether they were directly shared or appear as parent hierarchy. This makes it impossible to distinguish parent folder noise from real folder permission changes.

Additional testing

Tested all header combinations against the same delta token:

Environment

• API version: v1.0
• Authentication: Application permissions (client credentials)
• Service: SharePoint Online

未識別出任何儲存庫檔案或測試；從已記錄的 /drives/{drive-id}/root/delta 端點和列出的 Prefer 標頭開始，使用提供的權杖序列重現四項回應。當服務行為或其文件明確區分直接共用的資料夾與僅存在於階層中的資料夾，且預期的註解行為已獲得驗證時，即視為完成。