Feature Request: (webui) do not throw away message if there is error in stream

[ngxson]

Prerequisites

• I am running the latest code. Mention the version if possible as well.
• I carefully followed the README.md.
• I searched using keywords relevant to my issue to make sure that I am creating a new issue that is not already open (or closed).
• I reviewed the Discussions, and have a new and useful enhancement to share.

Feature Description

Currently, if the UI got an error while it's generating the text, it will throw away the generating message.

The most simple way to test is to Ctrl+C to kill the server while it's generating a response.

The expected behavior is to show a meaningful error like what they do on chatgpt

Motivation

N/A

Possible Implementation

No response

[maximizemaxwell]

Hi, I'd like to try this

[Aaryan-549]

I've created a pull request that fixes this issue: #14374

The fix preserves partial content when streaming errors occur and shows a user-friendly error message, similar to ChatGPT's behavior.

How it works:

• Enhanced the onChunk callback to handle streaming errors
• Added toast notifications for different error types
• Preserves partial response when connection is interrupted

Please review when you have a chance. Happy to make any adjustments!