Offline buffering does not buffer when server is offline

[Voidthe]

Describe the bug
When using cloudflare and cloudflare tunnels to access traccar if the tunnel or server is down location data is not cached.

To Reproduce
Steps to reproduce the behavior:

1. Turn off cloudflare tunnel
2. Observe client still sends updates but updates not reflected in traccar manager
3. Turn on cloudflare tunnel
4. Observe that the data is lost.

Expected behavior
Location data is stored untill the server is back online and data is sync as normal.

Smartphone (please complete the following information):

• Iphone 13
• OS: IOS 18
• Browser: IOS client
• Version: Latest

Additional context
I have a feeling its due to how traccar client checks if the server is online. I have a feeling that its only checking for normal failure codes like 4XX or 50X. When using cloudflare tunnel it will return a nonstandard error code of 530. It feels like it should only delete the data on a successful 2XX response

[tananaev]

https://github.com/traccar/traccar-client-ios/blob/master/TraccarClient/RequestManager.swift