Add support for Targeted Messages

[ShanmathiMayuramKrithivasan]

Adds support for targeted messages that only a specific recipient can see in a conversation.

Usage

// Target the sender from context
await context.Send(
    new MessageActivity("Only you see this!")
        .WithTargetedRecipient(true)
);

// Target a specific user
await context.Send(
    new MessageActivity("Private message")
        .WithTargetedRecipient("user-id")
);

Key Changes

• SDK appends ?isTargetedActivity=true to API calls, so backend services handles the messages accordingly
• Supports create, update, delete, and reply operations
• Includes tests and sample bot

[Copilot]

Pull request overview

This PR adds support for targeted messages in Microsoft Teams bots, allowing messages to be visible only to specific recipients within group conversations. The implementation includes SDK changes, API client methods, validation logic, comprehensive tests, and a sample application.

Changes:

• Added IsTargeted property and WithTargetedRecipient helper methods to MessageActivity
• Implemented CreateTargetedAsync, UpdateTargetedAsync, and DeleteTargetedAsync methods in ActivityClient
• Added routing logic to automatically use targeted endpoints when IsTargeted is true
• Added validation to ensure proactive targeted messages have explicit recipients
• Included unit tests for the new functionality and a complete sample application

Reviewed changes

Copilot reviewed 14 out of 14 changed files in this pull request and generated 9 comments.

Show a summary per file

File	Description
Tests/Microsoft.Teams.Api.Tests/Clients/ActivityClientTests.cs	Unit tests for ActivityClient targeted message methods (create, update, delete)
Tests/Microsoft.Teams.Api.Tests/Activities/Message/MessageActivityTests.cs	Unit tests for WithTargetedRecipient helper methods and JSON serialization
Samples/Samples.TargetedMessages/appsettings.json	Configuration file for sample application
Samples/Samples.TargetedMessages/appsettings.Development.json	Development-specific configuration for sample
Samples/Samples.TargetedMessages/Samples.TargetedMessages.csproj	Project file for targeted messages sample
Samples/Samples.TargetedMessages/README.md	Comprehensive documentation with examples and API details
Samples/Samples.TargetedMessages/Properties/launchSettings.json	Launch configuration for sample application
Samples/Samples.TargetedMessages/Program.cs	Sample bot demonstrating all targeted message operations
Microsoft.Teams.sln	Added sample project to solution
Libraries/Microsoft.Teams.Plugins/Microsoft.Teams.Plugins.AspNetCore/AspNetCorePlugin.cs	Routing logic to use targeted endpoints based on IsTargeted flag
Libraries/Microsoft.Teams.Apps/Contexts/Context.Send.cs	Auto-sets recipient to Activity.From for reactive targeted messages
Libraries/Microsoft.Teams.Apps/App.cs	Validates that proactive targeted messages have explicit recipients
Libraries/Microsoft.Teams.Api/Clients/ActivityClient.cs	API methods for targeted create, update, and delete operations
Libraries/Microsoft.Teams.Api/Activities/Message/MessageActivity.cs	Added IsTargeted property and WithTargetedRecipient methods

Comments suppressed due to low confidence (1)

Libraries/Microsoft.Teams.Api/Activities/Message/MessageActivity.cs:266

• The IsTargeted property is not merged in the Merge method, but other nullable properties like Importance, DeliveryMode, and Expiration are merged using the null-coalescing operator. For consistency with other nullable properties in MessageActivity, consider adding IsTargeted ??= from.IsTargeted; to the Merge method.

    public MessageActivity Merge(MessageActivity from)
    {
        base.Merge(from);

        Text ??= from.Text;
        Speak ??= from.Speak;
        InputHint ??= from.InputHint;
        Summary ??= from.Summary;
        TextFormat ??= from.TextFormat;
        AttachmentLayout ??= from.AttachmentLayout;
        SuggestedActions ??= from.SuggestedActions;
        Importance ??= from.Importance;
        DeliveryMode ??= from.DeliveryMode;
        Expiration ??= from.Expiration;
        Value ??= from.Value;
        AddAttachment(from.Attachments?.ToArray() ?? []);

        return this;
    }

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Pull request overview

Copilot reviewed 15 out of 15 changed files in this pull request and generated 3 comments.

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Pull request overview

Copilot reviewed 15 out of 15 changed files in this pull request and generated 1 comment.

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[rido-min]

approving for preview, there are still some details related to the Recipient before we get into stable a stable release.