Describe the bug

When I add a custom provider, it appears duplicated in the list. If I remove either of them, all of them are removed.

In model selection at chat, ithe provideralso appears duplicated.

One strange thing is that, if I select any of the duplicated providers in model selection, the models in model list appear duplicated.

Another very bad behavior is that, when I added a second custom provider, it not only got duplicated, but it displays API Host url settings from the previous provider, despite the fact I have configured it with the correct url. It would ignore what I typed and display info about the first custom provider.

To Reproduce
Steps to reproduce the behavior:

1. Go to Settings > Configure Providers > Add Custom Provier
2. Add a provider. I tried Z.ai and Cerebras
3. You will see that the custom provider will appear duplicated in the Providers list

Expected behavior
Only one custom provider should have been added.

Screenshots
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Please provide following information:

• OS & Arch: MacOS 15.5 Macbook M4
• Interface: UI
• Version: 1.9.3
• Extensions enabled: N/A
• Provider & Model: Z.ai GLM-4.6 and Cerebras Qwen3 Coder.

Additional context
Add any other context about the problem here.