Update Deployment Guide with Azure authentication steps

Added instructions for authenticating with Azure in VS Code Web.

Author: Thanusree-Microsoft

docs/DeploymentGuide.md

@@ -120,6 +120,8 @@ Select one of the following options to deploy the Content Processing Solution Ac
 <details>
 <summary><b>Option C: Visual Studio Code Web</b></summary>
 
+### VS Code Web
+
  [![Open in Visual Studio Code Web](https://img.shields.io/static/v1?style=for-the-badge&label=Visual%20Studio%20Code%20(Web)&message=Open&color=blue&logo=visualstudiocode&logoColor=white)](https://vscode.dev/azure/?vscode-azure-exp=foundry&agentPayload=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)
 
 1. Click the badge above (may take a few minutes to load)
@@ -132,13 +134,20 @@ Select one of the following options to deploy the Content Processing Solution Ac
     sh install.sh
     ```
     During this process, you’ll be prompted with the message:
+    <br> Choose “**Overwrite with versions from template**” and provide a unique environment name when prompted.
     ```
     What would you like to do with these files?
     - Overwrite with versions from template
     - Keep my existing files unchanged
     ```
-    Choose “**Overwrite with versions from template**” and provide a unique environment name when prompted.
-6. Proceed to [Step 3: Configure Deployment Settings](#step-3-configure-deployment-settings)
+    
+6. **Authenticate with Azure** (VS Code Web requires device code authentication):
+   
+   ```shell
+   az login --use-device-code
+   ```
+   > **Note:** In VS Code Web environment, the regular `az login` command may fail. Use the `--use-device-code` flag to authenticate via device code flow. Follow the prompts in the terminal to complete authentication.
+7. Proceed to [Step 3: Configure Deployment Settings](#step-3-configure-deployment-settings)
 
 </details>
 
@@ -544,4 +553,4 @@ Run the build and push script for your operating system:
 ./infra/scripts/docker-build.ps1
 ```
 
-> **Note:** These scripts will deploy your local code changes instead of pulling from the GitHub repository.
+> **Note:** These scripts will deploy your local code changes instead of pulling from the GitHub repository.