Move AI External Moderation into Safety & Compliance
## Summary
AI External Moderation is currently under "Tools & Automation", and is the only item under this heading in the base module. The "Safety & Compliance" heading would seem a better fit, and would allow "Tools & Automation" to be deprecated.
## Problem
This would tighten the menu structure, and group External Moderation with related items like AI Moderation Guardrails.
## Proposed solution _(optional)_
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## Workaround _(optional)_
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## Affected modules / components _(optional)_
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