Add scripts to detect whether a cluster is affected by CA-528 or not

[m4nti5]

This PR adds two scripts:

find_candidate_collections.js Metadata scan — finds collections that could be affected
find_duplicates.js Aggregation — confirms whether duplicates actually exist

To detect wheter you might or are affected by CA-528. The main reason it's two script is because the second script does a collection scan with an aggregation, so, the idea is that a customer that is not sure it might be affected can run the first script to check for the metadata of all the collections and find whether the cluster might be affected or not.

[Copilot]

Pull request overview

This PR adds a two-step diagnostic workflow under ca-528/ to help support/field teams determine whether a sharded MongoDB cluster is affected by SERVER-85346 (CA-528), by first identifying candidate collections via metadata and then running an aggregation-based confirmation step.

Changes:

• Added a README-based “Detection Guide” describing the two-step process and expected outputs.
• Added find_candidate_collections.js to quickly scan sharded collections’ index/collection collation metadata.
• Added find_duplicates.js to run an aggregation over candidate collections to report potential duplicate groups.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 5 comments.

File	Description
ca-528/README.md	Adds end-to-end operator documentation for running Step 1/Step 2 and interpreting results.
ca-528/find_candidate_collections.js	Introduces a fast metadata scan to list collections/indexes that may require deeper checking.
ca-528/find_duplicates.js	Introduces an aggregation-based scan intended to confirm duplicate groups for candidate indexes/collections.

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[rafael-mdb]

No blocking issues. LGTM.
I tested against controlled Sharded cluster collation duplicate scenarios with multiple duplicate groups and verified correct detection and reporting.