Throws and exception for radial search when mapping is for on-disk mode

[shatejas]

Description

• Adds a debug log for time spent rescoring

Related Issues

Resolves #[Issue number to be closed when this PR is merged]

Check List

• [x] New functionality includes testing.
• [ ] New functionality has been documented.
• [ ] API changes companion pull request created.
• [x] Commits are signed per the DCO using --signoff.
• [ ] Public documentation issue/PR created.

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