Remove supports_threading guard from app.reply()

[corinagum]

Summary

• Remove supports_threading() guard from app.reply() 3-arg form -- always calls to_threaded_conversation_id() when message_id is provided
• Remove supports_threading() function and THREADING_SUFFIXES constant (dead code)
• Remove supports_threading tests
• Update test manual example to remove conversation type guard
• Threading support is now determined by the service, not the SDK

Why: Threading support is expanding (channels, 1:1, group chats). Maintaining an allowlist of conversation ID suffixes creates a maintenance burden and can block developers from using newly supported scopes until the SDK is updated.

Test plan

• ruff check: all passed
• pyright: 0 errors
• pytest: 630 passed

🤖 Generated with Claude Code

[Copilot]

Pull request overview

Removes the SDK-side allowlist/guard for threaded replies so App.reply() consistently constructs a threaded conversation id when a message_id is provided, delegating “does this scope support threading?” to the Teams service.

Changes:

• Remove supports_threading() and THREADING_SUFFIXES, and delete the related unit tests.
• Update App.reply() 3-arg form to always call to_threaded_conversation_id() when message_id is provided.
• Simplify the threading example by removing the local conversation-type guard and update its README accordingly.

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
packages/apps/tests/test_thread.py	Removes supports_threading tests; keeps to_threaded_conversation_id coverage.
packages/apps/src/microsoft_teams/apps/utils/thread.py	Deletes supports_threading + suffix allowlist; retains only to_threaded_conversation_id.
packages/apps/src/microsoft_teams/apps/app.py	Updates App.reply() to always thread in 3-arg form and adjusts docstring/imports.
examples/threading/src/main.py	Removes manual “conversation type supports threading” guard in the sample.
examples/threading/README.md	Updates sample documentation to match new behavior/expectations.