fix(metrics): addDimensions() documentation and tests

[matteofigus]

Fix: addDimensions() should create a set

Summary

Changes

This PR fixes issue #3777 where addDimensions() was incorrectly adding dimensions to the existing set instead of creating a new dimension set.

Changes made:

1. Fixed the addDimensions() method in Metrics.ts to create a new dimension set rather than adding to existing dimensions
2. Added a dimensionSets array to store multiple dimension sets
3. Updated the metrics serialization logic to handle multiple dimension sets
4. Added unit tests to verify the correct behavior of dimension sets
5. Updated documentation to explain the correct behavior of addDimensions()

Documentation updates:

• Added a new section in the metrics documentation explaining how to use dimension sets
• Created a new code example showing how to use addDimensions() to create multiple dimension sets
• Clarified that addDimensions() creates a new set rather than modifying existing dimensions

Issue number: #3777

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[boring-cyborg]

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[matteofigus]

Thanks for catching this! I've reverted the types/index.ts file to its original state. This was an unintended change that happened during the implementation. The PR now only contains documentation updates and test fixes.

[dreamorosi]

Hi @matteofigus, I'll pick up the review for this right after the release of Bedrock Agent Functions on Tue 06/03.

[sonarqubecloud]

Quality Gate passed

Issues
1 New issue
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud