This pull request updates the Teams SDK C# documentation to focus exclusively on the minimal API approach, removing all references, code samples, and explanations related to the legacy controller-based pattern. The changes streamline the docs, making them clearer and more consistent for new users by presenting a single recommended way to build Teams apps with C#.

Key changes include:

Removal of Controller-based Examples and Tabs

• All controller/attribute-based code samples and associated <Tabs> UI have been removed from the following documentation files, leaving only minimal API examples using app.OnMessage, teams.OnMessage, etc. (teams.md/src/components/include/essentials/api/csharp.incl.md, teams.md/src/components/include/essentials/graph/csharp.incl.md, teams.md/src/components/include/essentials/on-activity/csharp.incl.md, teams.md/src/components/include/essentials/sending-messages/csharp.incl.md, teams.md/src/components/include/essentials/sending-messages/proactive-messaging/csharp.incl.md, teams.md/src/components/include/getting-started/code-basics/csharp.incl.md, teams.md/src/components/include/in-depth-guides/adaptive-cards/building-adaptive-cards/csharp.incl.md, teams.md/src/components/include/in-depth-guides/ai/mcp/mcp-client/csharp.incl.md) [1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11] [12] [13] [14]

Updates to Getting Started and Code Basics

• The getting started guide and code basics now exclusively show minimal API setup and message handling using teams.OnMessage, removing all mention of controller classes and attributes. Project structure and code samples have been updated accordingly. [1] [2] [3]

Improvements to Adaptive Card Action Handling

• Adaptive card action handling is refactored to use the minimal API pattern (teams.OnAdaptiveCardAction) instead of controller attributes. The handler logic is also updated for clarity and additional action handling, with improved logging and response construction. [1] [2]

General Documentation Clean-up

• Explanations and comments have been updated to refer to the minimal API approach, and parameter names have been adjusted for consistency (e.g., context.activity instead of activity). [1] [2]

Migration and Dependency Updates

• Removed unnecessary service registrations related to controllers in migration guides and updated dependency usage in code samples to match the minimal API pattern. [1] [2]

These changes ensure the documentation is modern, easier to follow, and aligned with the current best practices for building Teams apps in C#.