Decouple NpmAuthenticateV0 from packaging-common/npm modules

[AlexVTor]

Context

packaging-common/npm/ is a shared package consumed by three tasks: NpmAuthenticateV0, NpmV1, and DownloadGitHubNpmPackageV1. Despite being "shared," each task uses a different subset of the package. The shared abstraction adds dependency coupling and test complexity without meaningful code reuse. This PR will decouple the dependency on a package from the separate repo, while providing the same utility in an improved manner.

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Task Name

NpmAuthenticateV0

Description

What changed:

• Inlined registry parsing, URL normalization, credential formatting, and file I/O (~120 lines replacing 3 external module imports)

• Replaced the NpmRegistry class with a local NpmrcCredential interface

• Extracted credential resolution into npmrcCredential.ts and backup management into npmrcBackupManager.ts

• Consolidated the duplicated WIF auth branches into a single check

• Improved variable naming throughout (endpointsArray → previouslyAuthenticatedUrls, registry → npmrcEntry, etc.)

• Rewrote tests to exercise real code paths instead of mocking our own logic

The only remaining packaging-common dependency is locationUtilities (for Azure DevOps service location), which is a general-purpose module used across many tasks.

Risk Assessment (Low / Medium / High)

Medium

Change Behind Feature Flag (Yes / No)

Can this change be behine feature flag, if not why?

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Tech Design / Approach

• Design has been written and reviewed.
• Any architectural decisions, trade-offs, and alternatives are captured.

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Documentation Changes Required (Yes/No)

Indicate whether related documentation needs to be updated.

• User guides, API specs, system diagrams, or runbooks are updated.
  N/A

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Unit Tests Added or Updated (Yes / No)

Indicate whether unit tests were added or modified to reflect these changes.
Y

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Additional Testing Performed

List all other tests performed (manual or automated, including integration, regression, scenario tests, etc.).
Local, E2E, Testing Pipelines

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Logging Added/Updated (Yes/No)

• Appropriate log statements are added with meaningful messages.
• Logging does not expose sensitive data.
• Log levels are used correctly (e.g., info, warn, error).
  Y

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Telemetry Added/Updated (Yes/No)

• Custom telemetry (e.g., counters, timers, error tracking) is added as needed.
• Events are tagged with proper metadata for filtering and analysis.
• Telemetry is validated in staging or test environments.
  N

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Rollback Scenario and Process (Yes/No)

• Rollback plan is documented.
  Rollback via task override can be applied to revert to a previous version

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Dependency Impact Assessed and Regression Tested (Yes/No)

• All impacted internal modules, APIs, services, and third-party libraries are analyzed.
• Results are reviewed and confirmed to not break existing functionality.
  Y

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Checklist

• Related issue linked (if applicable)
• Task version was bumped — see versioning guide
• Verified the task behaves as expected

[AlexVTor]

/azp run

[azure-pipelines]

Azure Pipelines successfully started running 3 pipeline(s).

[AlexVTor]

/azp run

[azure-pipelines]

Azure Pipelines successfully started running 3 pipeline(s).