Update copy files task to use fast glob

[sasandhu]

Context

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CopyFiles@2 task fails to copy files if the source folder is very large with javascript heap out of memory issues. This is because the find function tries to loads the whole source folder into memory before matching with the file pattern glob.

Task Name

Name of the updated or newly created pipeline task.

CopyFiles@2

Description

Summarize the changes made in this PR clearly and concisely.

Use fast-glob instead of tl.find

Risk Assessment (Low / Medium / High)

Assess the level of risk and provide reasoning (e.g., scope, impact, backward compatibility).

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.

None

Documentation Changes Required (Yes/No)

Indicate whether related documentation needs to be updated.

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

None

Unit Tests Added or Updated (Yes / No)

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

No, since the functionality is the same

Additional Testing Performed

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

None

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).

No

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.

No

Rollback Scenario and Process (Yes/No)

• Rollback plan is documented.

No

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.

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Checklist

• Related issue linked - [enhancement]: Make CopyFiles usable to copy single files out of source folders with a lot of subfolders/subpaths #20281
• Task version was bumped — see versioning guide
• Verified the task behaves as expected