[BUG] [Web UI] ProviderIcon renders empty space for custom/unknown providers #15294

Description

In the web UI, when using a custom provider that isn't in the built-in icon set, ProviderIcon renders an empty SVG <use> reference that points to a nonexistent sprite ID, resulting in blank space where the icon should be.

This affects the model selector in the prompt bar, provider settings, model settings, the connect provider dialog, and the enterprise share page.

Filed a PR to fix the same, #15295.

Plugins

None

OpenCode version

1.2.15

Steps to reproduce

1. Configure a custom provider not in the built-in icon set
2. Select a model from that provider
3. Observe blank space where the provider icon should be in the prompt bar model selector

Screenshot and/or share link

Before	After PR #15295

Operating System

Ubuntu 24.04

Terminal

No response