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 send(MessageActivityInput(text="Only you see this").with_targeted_recipient(True))

# Target a specific user
await send(MessageActivityInput(text="Private").with_targeted_recipient("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 example bot

[Copilot]

Pull request overview

Adds first-class support for “targeted” (recipient-scoped) message activities by routing targeted sends/updates through specialized conversation APIs and providing an example bot.

Changes:

• Add is_targeted + with_targeted_recipient(...) on MessageActivityInput to mark messages as targeted and optionally set a recipient.
• Route app-layer sends/updates to new API client methods that append ?isTargetedActivity=true.
• Add an example app and unit tests covering the new model/client surfaces.

Reviewed changes

Copilot reviewed 11 out of 12 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
uv.lock	Adds the new examples/targeted-messages workspace package to the lock/workspace members.
packages/apps/src/microsoft_teams/apps/routing/activity_context.py	Infers recipient for targeted sends in reactive contexts (sender-targeted).
packages/apps/src/microsoft_teams/apps/http_plugin.py	Chooses targeted vs non-targeted create/update API routes based on is_targeted.
packages/apps/src/microsoft_teams/apps/app.py	Validates proactive targeted sends require an explicit recipient.
packages/api/tests/unit/test_message_activities.py	Adds tests for with_targeted_recipient and serialization of isTargeted.
packages/api/tests/unit/test_conversation_client.py	Adds tests for the new targeted activity operations.
packages/api/src/microsoft_teams/api/clients/conversation/client.py	Exposes create_targeted/update_targeted/delete_targeted on activity operations.
packages/api/src/microsoft_teams/api/clients/conversation/activity.py	Implements targeted create/update/delete URLs using isTargetedActivity=true.
packages/api/src/microsoft_teams/api/activities/message/message.py	Introduces is_targeted field and builder method with_targeted_recipient.
examples/targeted-messages/src/main.py	Adds a runnable bot demonstrating targeted send/reply/update/delete flows.
examples/targeted-messages/pyproject.toml	Adds new example package definition and dependencies.
examples/targeted-messages/README.md	Documents commands and how targeted messages work.

[heyitsaamir]

minor comments, but overall looks good. Once you make these changes, I'll merge it