v5 loadExternalTokens fixes

[tnorling]

This pull request introduces improvements and bug fixes to the external token loading logic in the MSAL browser library, focusing on correct authority/environment handling, refresh token expiration, and telemetry enhancements. It also updates and adds new tests to ensure proper caching behavior and coverage for new features.

Token caching and authority/environment handling:

• The authority discovery logic in TokenCache.ts now uses AuthorityFactory.createDiscoveredInstance, ensuring that the preferred cache environment (e.g., login.windows.net) is used when storing tokens, rather than the canonical authority string. This affects how accounts and tokens are keyed and cached. [1] [2]
• The code now consistently passes non-optional authority and idTokenClaims parameters in token/account generation and caching functions, simplifying error handling and ensuring correct environment assignment. [1] [2] [3] [4]

Refresh token expiration and telemetry:

• When refresh_token_expires_in is present in the external token response, the code calculates and stores an explicit expiration time for the refresh token. This value is also added to telemetry as extRtExpiresOnSeconds for monitoring. [1] [2] [3] [4]
• The PerformanceEvent type is updated to include new telemetry fields (acntLoggedOut, extRtExpiresOnSeconds) for improved diagnostics. [1] [2]

Test improvements and coverage:

• New tests verify that refresh tokens are cached with the correct expiration time when refresh_token_expires_in is provided, and without expiration when it is absent. Additional tests confirm that the preferred cache environment is used for all token types.
• Test data and expectations are updated to match the new preferred cache logic, such as using login.windows.net for environment values.
• Redundant tests for error cases involving authority are removed, reflecting the new requirements for token loading.

Miscellaneous:

• Minor improvements in type safety and code clarity, such as removing optional chaining where values are guaranteed to be present. [1] [2]
• Additional test utilities and spies are added to support new test scenarios. [1] [2]

These changes collectively improve correctness, reliability, and observability of external token loading and caching in the browser library.

[Copilot]

Pull request overview

This pull request introduces bug fixes and enhancements to the external token loading (loadExternalTokens) functionality in MSAL browser and common libraries. The changes focus on improving authority/environment handling, implementing refresh token expiration tracking, and enhancing telemetry for better observability.

Changes:

• Authority handling now uses AuthorityFactory.createDiscoveredInstance to ensure tokens are cached with the preferred cache environment (e.g., login.windows.net)
• Refresh token expiration is calculated and stored when refresh_token_expires_in is provided in the response
• New telemetry fields (acntLoggedOut, extRtExpiresOnSeconds) added for improved diagnostics
• Account validation logic improved to use getAllAccounts with filters for better alias support
• Tenant profile handling enhanced to ensure home tenant profile is always present

Reviewed changes

Copilot reviewed 13 out of 13 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
lib/msal-browser/src/cache/TokenCache.ts	Core changes to use AuthorityFactory for proper environment handling, non-optional authority parameter, and refresh token expiration calculation
lib/msal-browser/src/cache/BrowserCacheManager.ts	Removed unnecessary optional chaining for result.account properties (now guaranteed non-null)
lib/msal-browser/test/cache/TokenCache.spec.ts	Comprehensive test additions for refresh token expiration, preferred cache environment, and removal of obsolete authority error test
lib/msal-common/src/response/ResponseHandler.ts	Improved account validation using getAllAccounts with filters and added telemetry for logged-out accounts
lib/msal-common/src/cache/utils/AccountEntityUtils.ts	Enhanced to ensure home tenant profile always exists in getAccountInfo and createAccountEntityFromAccountInfo
lib/msal-common/src/telemetry/performance/PerformanceEvent.ts	Added new telemetry fields: acntLoggedOut and extRtExpiresOnSeconds
lib/msal-common/test/response/ResponseHandler.spec.ts	New tests for handling refresh token responses with account alias validation
lib/msal-common/test/cache/AccountEntityUtils.spec.ts	Updated test expectations for home tenant profile creation
lib/msal-node/test/client/PublicClientApplication.spec.ts	Added getAllAccounts mock for test compatibility
lib/msal-browser/test/interaction_client/SilentRefreshClient.spec.ts	Added getAllAccounts mock for test compatibility
lib/msal-common/apiReview/msal-common.api.md	Updated API surface to reflect new telemetry fields
change/@azure-msal-common-*.json	Beachball change file for msal-common package
change/@azure-msal-browser-*.json	Beachball change file for msal-browser package