docs: Add documentation on how to contribute a Vector DB provider and

updated Test documentation and added a shortcut

Signed-off-by: Francisco Javier Arceo <farceo@redhat.com>

docs/source/providers/inference/index.md

@@ -29,6 +29,7 @@ remote_runpod
 remote_sambanova
 remote_tgi
 remote_together
+remote_vertexai
 remote_vllm
 remote_watsonx
 ```

docs/source/providers/inference/remote_vertexai.md

@@ -0,0 +1,40 @@
+# remote::vertexai
+
+## Description
+
+Google Vertex AI inference provider enables you to use Google's Gemini models through Google Cloud's Vertex AI platform, providing several advantages:
+
+• Enterprise-grade security: Uses Google Cloud's security controls and IAM
+• Better integration: Seamless integration with other Google Cloud services
+• Advanced features: Access to additional Vertex AI features like model tuning and monitoring
+• Authentication: Uses Google Cloud Application Default Credentials (ADC) instead of API keys
+
+Configuration:
+- Set VERTEX_AI_PROJECT environment variable (required)
+- Set VERTEX_AI_LOCATION environment variable (optional, defaults to us-central1)
+- Use Google Cloud Application Default Credentials or service account key
+
+Authentication Setup:
+Option 1 (Recommended): gcloud auth application-default login
+Option 2: Set GOOGLE_APPLICATION_CREDENTIALS to service account key path
+
+Available Models:
+- vertex_ai/gemini-2.0-flash
+- vertex_ai/gemini-2.5-flash
+- vertex_ai/gemini-2.5-pro
+
+## Configuration
+
+| Field | Type | Required | Default | Description |
+|-------|------|----------|---------|-------------|
+| `project` | `<class 'str'>` | No |  | Google Cloud project ID for Vertex AI |
+| `location` | `<class 'str'>` | No | us-central1 | Google Cloud location for Vertex AI |
+
+## Sample Configuration
+
+```yaml
+project: ${env.VERTEX_AI_PROJECT:=}
+location: ${env.VERTEX_AI_LOCATION:=us-central1}
+
+```
+