[Inference] Fix Azure hostname check (elastic#222499)

## Summary

Fixes the Azure hostname check 

### Checklist

- [x] [Unit or functional
tests](https://www.elastic.co/guide/en/kibana/master/development-tests.html)
were updated or added to match the most common scenarios

Author: darnautov

x-pack/platform/packages/shared/ai-infra/inference-common/src/connectors/get_connector_model.test.ts

@@ -0,0 +1,49 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License
+ * 2.0; you may not use this file except in compliance with the Elastic License
+ * 2.0.
+ */
+
+import { type InferenceConnector, InferenceConnectorType } from './connectors';
+import { getConnectorModel } from './get_connector_model';
+
+describe('getConnectorModel', () => {
+  describe('Azure hostname check', () => {
+    it('should return a model from the Azure URL', () => {
+      const connector = {
+        type: InferenceConnectorType.OpenAI,
+        config: {
+          apiUrl: 'https://azure.com/v1/models/gpt-4',
+        },
+      } as unknown as InferenceConnector;
+
+      const model = getConnectorModel(connector);
+      expect(model).toBe('gpt-4');
+    });
+
+    it('should return a model from the Azure URL with subdomain', () => {
+      const connector = {
+        type: InferenceConnectorType.OpenAI,
+        config: {
+          apiUrl: 'https://subdomain.azure.com/v1/models/gpt-4o',
+        },
+      } as unknown as InferenceConnector;
+
+      const model = getConnectorModel(connector);
+      expect(model).toBe('gpt-4o');
+    });
+
+    it('should return undefined for unsupported API URL', () => {
+      const connector = {
+        type: InferenceConnectorType.OpenAI,
+        config: {
+          apiUrl: 'https://fake-azure.com/v1/models/unknown-model',
+        },
+      } as unknown as InferenceConnector;
+
+      const model = getConnectorModel(connector);
+      expect(model).toBeUndefined();
+    });
+  });
+});

x-pack/platform/packages/shared/ai-infra/inference-common/src/connectors/get_connector_model.ts

@@ -41,10 +41,9 @@ const OPENAI_MODEL_NAMES = [
 
 function getOpenAiModelFromUrl(apiUrl: string) {
   const url = new URL(apiUrl);
-  if (url.hostname.endsWith('azure.com')) {
+  if (url.hostname === 'azure.com' || url.hostname.endsWith('.azure.com')) {
     return OPENAI_MODEL_NAMES.find((modelName) => {
       return url.pathname.includes(modelName);
     });
   }
-  return undefined;
 }