Add device code flow when not brokered

[TylerLeonhardt]

fixes #270452

[Copilot]

Pull Request Overview

This PR adds device code flow authentication support when not brokered for the Microsoft Authentication extension. This provides an alternative authentication method for environments where traditional browser-based flows are not available or when broker authentication is not supported.

Key changes:

• Added device code flow as a new authentication method with support for different extension host environments
• Enhanced flow selection logic to consider client support and broker availability
• Integrated device code flow UI with clipboard integration and progress notifications

Reviewed Changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
extensions/microsoft-authentication/src/node/flows.ts	Adds DeviceCodeFlow class and updates flow selection logic to consider client support and broker availability
extensions/microsoft-authentication/src/node/cachedPublicClientApplication.ts	Implements device code authentication with user interaction and progress handling
extensions/microsoft-authentication/src/node/authProvider.ts	Updates authentication provider to determine client support and pass callback URI to flows
extensions/microsoft-authentication/src/common/publicClientCache.ts	Adds device code method to the cached client interface
extensions/microsoft-authentication/src/common/loopbackClientAndOpener.ts	Refactors to accept callback URI as constructor parameter instead of computing it
extensions/microsoft-authentication/src/node/test/flows.test.ts	Adds comprehensive test coverage for the new flow selection logic
extensions/microsoft-authentication/src/common/test/loopbackClientAndOpener.test.ts	Updates test to accommodate new constructor parameter and skips problematic test