feat: add OpenAI model support

Adds support for OpenAI models, allowing users to leverage various OpenAI models directly from the application. This includes custom OpenAI models and OpenAI-specific configurations for seamless integration.

src/components/Common/ProviderIcon.tsx

@@ -1,4 +1,4 @@
-import { ChromeIcon } from "lucide-react"
+import { ChromeIcon, CloudCog } from "lucide-react"
 import { OllamaIcon } from "../Icons/Ollama"
 
 export const ProviderIcons = ({
@@ -11,6 +11,8 @@ export const ProviderIcons = ({
   switch (provider) {
     case "chrome":
       return <ChromeIcon className={className} />
+    case "custom":
+      return <CloudCog className={className} />
     default:
       return <OllamaIcon className={className} />
   }