Sync of read-only shared folder has permission issues since many versions (Windows)

### ⚠️ Before submitting, please verify the following: ⚠️

- [x] This is a **bug**, not a question or a configuration issue.
- [x] This issue is **not** already reported on Github (I have searched for it).
- [x] Nextcloud Server and Desktop Client are **up to date**. See [Server Maintenance and Release Schedule](https://github.com/nextcloud/server/wiki/Maintenance-and-Release-Schedule) and [Desktop Releases](https://nextcloud.com/install/#install-clients) for supported versions.
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### Bug description

Since many versions (I guess 3.10) successfull sync of our shared datas is broken. We've got ~80 GB with ~ 30000 files, shared to a group of employees.
This share is restricted to
- download and sync
- read-only
- share
Seems to be a problem on Linux, too:
https://github.com/nextcloud/desktop/issues/9488

On a fresh installed Windows 11 with current NextCloud Desktop (34.0.1rc1) sync of this files failes with permission WindowsError 5.

There are (I assume fully synced) temp files left:

This temp files have wrong permission on Windows-Filesystem - so they never could be renamed correctly:

### Steps to reproduce

1. Install current NextCloud Client on Windows 11 (NTFS-Filesystem) and try described share-permissions from above:

2. Let them sync.

### Expected behavior

A full and correctly named sync of my files.

### Which files are affected by this bug

Every file, shared with read-only permissions.

### Operating system

Windows

### Which version of the operating system you are running.

Windows 11

### Installation method

Official Windows MSI

### Nextcloud Server version

34.0.0

### Nextcloud Desktop Client version

34.0.0rc1

### Did this occur after an update or on a clean installation?

Clean desktop client installation

### Are you using the Nextcloud Server Encryption module?

No

### Are you using an external user-backend?

- [ ] Default internal user-backend
- [x] LDAP or Active Directory
- [ ] SSO - SAML
- [ ] Other

### Nextcloud Server logs

```shell
There are no related logs.
```

### Additional info

Workaround:
- changing permission on Windows-Filesystem
- delete issued folder
- change permissions on server to full-access
- sync
But I really need "read-only" restriction!

Partially logfile:
[20260614_1126_nextcloud.log.0.gz](https://github.com/user-attachments/files/28925545/20260614_1126_nextcloud.log.0.gz)