feat: support broker authentication for VSC and CLI

[HuihuiWu-Microsoft]

Support authentication in broker for following flows:

1. VSC m365 login
2. CLI m365 interactive login
3. CLI azure interactive login
   ADO: https://msazure.visualstudio.com/Microsoft%20Teams%20Extensibility/_workitems/edit/33871096/?view=edit

Screenshots:

Details
1> Introduced @azure/msal-node-extension package to add NativeBrokerPlugin for broker authentication support for both VSC and CLI
2> Added a feature toggle to control whether it's applying browser or broker auth
3> Added package mocks for keytar since it's not needed but required by the @azure/msal-node-extension package. Also updated UT mocks to by pass keytar loading
4> Bundle native node modules for @azure/msal-node-extension package including .node and .dll files into VSC extension
5> Upgraded APIs for auth code flow since the legacy API doesn't support broker auth
6> Upgraded typescript and ts node packages for compatibility

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 89.44%. Comparing base (c119326) to head (e729d60).
⚠️ Report is 30 commits behind head on dev.

Additional details and impacted files

@@           Coverage Diff            @@
##              dev   #14925    +/-   ##
========================================
  Coverage   89.44%   89.44%            
========================================
  Files         605      606     +1     
  Lines       37157    37210    +53     
  Branches     7449     7602   +153     
========================================
+ Hits        33236    33284    +48     
- Misses       1836     1838     +2     
- Partials     2085     2088     +3     

Files with missing lines	Coverage Δ
...ckages/cli/src/commonlib/common/tokenCacheUtils.ts	100.00% <100.00%> (ø)
packages/fx-core/src/common/featureFlags.ts	96.92% <100.00%> (+0.09%)	⬆️

... and 6 files with indirect coverage changes

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[Copilot]

Pull request overview

This PR adds broker authentication support to enable more secure authentication flows for Microsoft 365 logins in VSCode extension and CLI. The changes implement Windows Authentication Broker (WAM) support using MSAL's native broker plugin for improved user authentication experience.

Key Changes

• Integrated @azure/msal-node-extensions to enable broker-based authentication on Windows
• Added fallback logic between broker and browser authentication flows
• Implemented platform-specific native module handling for keytar and msal-node-runtime
• Created utility functions for token cache management

Reviewed changes

Copilot reviewed 23 out of 41 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
packages/vscode-extension/src/commonlib/m365Login.ts	Added broker plugin configuration with Windows platform check
packages/vscode-extension/src/commonlib/codeFlowLogin.ts	Implemented new loginWithBroker method and refactored token acquisition logic
packages/vscode-extension/src/commonlib/common/tokenCacheUtils.ts	Added utility function for account lookup by homeAccountId
packages/vscode-extension/esbuild.mjs	Added native module copying for Windows MSAL binaries
packages/vscode-extension/packageMocks/keytar/*	Created mock keytar implementation to avoid native module issues
packages/vscode-extension/package.json	Added msal-node-extensions dependency and enabled nativeWindowHandle API
packages/fx-core/src/common/featureFlags.ts	Added BrokerAuth feature flag
pnpm-workspace.yaml	Added keytar to onlyBuiltDependencies

Files not reviewed (2)

• packages/api/pnpm-lock.yaml: Language not supported
• packages/fx-core/pnpm-lock.yaml: Language not supported

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[tecton]

Translation file changes should be removed.