Ji/appmod dotnet containerization (#48564)

*App mod containerization flow

Author: jidddddd

docs/azure/migration/appmod/containerization.md

@@ -0,0 +1,64 @@
+---
+title: Containerize your project using GitHub Copilot app modernization for .NET
+description: Learn how to containerize your .NET project using GitHub Copilot app modernization for .NET.
+#customer intent: As a .NET developer, I want to containerize my project using GitHub Copilot App Modernization so that I can modernize my application efficiently.
+ms.topic: quickstart
+ms.custom: devx-track-dotnet
+ms.date: 09/17/2025
+author: JiDong
+ms.author: donji
+---
+
+# Quickstart: Containerize your project using GitHub Copilot app modernization for .NET
+
+In this quickstart, you learn how to containerize your project using GitHub Copilot app modernization for .NET. The app modernization tooling uses GitHub Copilot's AI capabilities to:
+
+- Analyze your project structure and dependencies
+- Generate Dockerfile configurations
+- Create build-ready Docker images
+- Guide you through the containerization process
+
+## Prerequisites
+
+Before you begin, make sure you have:
+
+- Windows operating system
+- [Visual Studio 2022 version 17.14.16 or newer](https://visualstudio.microsoft.com/downloads/)
+- [.NET desktop development workload](/visualstudio/install/modify-visual-studio?view=vs-2022&preserve-view=true#change-workloads-or-individual-components) with these optional components enabled:
+  - GitHub Copilot
+  - GitHub Copilot app modernization for .NET
+- GitHub account with Copilot access and a supported subscription plan:
+  - [Sign in to Visual Studio using a GitHub account](/visualstudio/ide/work-with-github-accounts) with [Copilot access](https://docs.github.com/copilot/about-github-copilot/what-is-github-copilot#getting-access-to-copilot).
+  - Supported subscription plans: Copilot Pro, Copilot Pro+, Copilot Business, or Copilot Enterprise.
+  - If you change subscriptions, restart Visual Studio.
+
+## Containerize your project
+
+The GitHub Copilot app modernization for .NET containerization feature helps you containerize your project. To start the containerization process, complete the following steps:
+
+1. Open your project in Visual Studio.
+
+1. Start containerization by using one of these approaches:
+
+    - **Containerize from Assessment Report**: In the assessment report, select **Run Task** for the Docker Containerization issue.
+
+        :::image type="content" source="media/containerize-assessment-report.png" alt-text="Screenshot that shows containerization task in assessment report.":::
+
+    - **Use a containerization prompt**: You can input the following prompt in Copilot chat to containerize your project:
+
+        *Scan my project and help me plan how to containerize my application using the #appmod-get-containerization-plan tool. Execute the plan. The end goal is to have Dockerfiles that are able to be built.*
+
+        :::image type="content" source="media/containerization-prompt.png" alt-text="Screenshot that shows how to start the containerization process in GitHub Copilot using a prompt.":::
+
+1. After you start the process, GitHub Copilot can ask for your approval to use tools or run commands. Grant permission when prompted.
+
+1. GitHub Copilot analyzes your project and generates a plan. The plan includes a breakdown of your project and steps for containerizing your project.
+
+1. GitHub Copilot follows the steps to generate a Dockerfile and validate that your Docker image builds successfully.
+
+1. When GitHub Copilot finishes containerizing your project, it provides a summary of what it did.
+
+## Notes
+
+- Use Claude Sonnet 4 or later models for the best results.
+- Copilot might take a few iterations to fix containerization errors.

docs/azure/migration/appmod/media/containerization-prompt.png

@@ -33,6 +33,8 @@ items:
         - name: Predefined Tasks
           href: ./migration/appmod/predefined-tasks.md
         - name: Quickstart - Assess and migrate a .NET project
+          href: ./migration/appmod/containerization.md
+        - name: Quickstart - Containerize a .NET project
           href: ./migration/appmod/quickstart.md
         - name: Quickstart - Deploy a .NET project to Azure
           href: ./migration/appmod/deploy.md