fix: upgrade @ai-sdk/azure to v3 and use deployment-based URLs

- Upgrade @ai-sdk/azure from ^2.0.6 to ^3.0.26
  - v3 defaults provider(id) to Responses API (works for all models)
  - v2 defaulted to Chat Completions, breaking codex models
- Add useDeploymentBasedUrls: true to createAzure()
  - Produces /deployments/{id}/{path} URLs (universally compatible)
  - Without it, SDK uses /v1/{path} which only works on AI Foundry resources

src/api/providers/azure.ts

@@ -35,11 +35,15 @@ export class AzureHandler extends BaseProvider implements SingleCompletionHandle
 		this.options = options
 
 		// Create the Azure provider using AI SDK
-		// The @ai-sdk/azure package uses resourceName-based routing
+		// The @ai-sdk/azure package uses resourceName-based routing.
+		// useDeploymentBasedUrls produces the universally compatible
+		// /deployments/{id}/{path} URL shape that works on both classic
+		// Azure OpenAI resources and newer AI Foundry resources.
 		this.provider = createAzure({
 			resourceName: options.azureResourceName ?? "",
 			apiKey: options.azureApiKey, // Optional — Azure supports managed identity / Entra ID auth
 			apiVersion: options.azureApiVersion ?? azureOpenAiDefaultApiVersion,
+			useDeploymentBasedUrls: true,
 			headers: DEFAULT_HEADERS,
 		})
 	}

src/package.json

@@ -451,7 +451,7 @@
 	},
 	"dependencies": {
 		"@ai-sdk/amazon-bedrock": "^4.0.50",
-		"@ai-sdk/azure": "^2.0.6",
+		"@ai-sdk/azure": "^3.0.26",
 		"@ai-sdk/baseten": "^1.0.31",
 		"@ai-sdk/cerebras": "^1.0.0",
 		"@ai-sdk/deepseek": "^2.0.14",