Add an api endpoint to get mon addresses

[sabaini]

Description

Please include a summary of the changes and the related issue. Please also include relevant motivation and context. List any dependencies that are required for this change.

Fixes # (issue)

Type of change

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• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• CleanCode (Code refactor, test updates, does not introduce functional changes)
• Documentation update (Doc only change)

How Has This Been Tested?

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Please describe the addition/modification of tests done to verify this change. Please also list any relevant details for your test configuration.

Contributor's Checklist

Please check that you have:

• self-reviewed the code in this PR.
• added code comments, particularly in hard-to-understand areas.
• updated the user documentation with corresponding changes.
• added tests to verify effectiveness of this change.

[UtkarshBhatthere]

+1 lgtm, a functional test on this API could be very beneficial (will also verify the cleanup of mon.host entries).

[lmlg]

lgtm