Add byok migration script for newly hosted keys #3462

Bugbot Review

Bugbot Analysis Progress (4m 16s elapsed)

✅ Gathered PR context (2s)
✅ Completed bug detection (3m 46s)
✅ Posted analysis results (28s)

Final Result: Bugbot completed review and found 1 potential issue.

Request ID: serverGenReqId_2e392fd2-f252-41f6-b1d2-ce9894908d06

Cursor Bugbot has reviewed your changes and found 1 potential issue.

^{Bugbot Autofix is OFF. To automatically fix reported issues with cloud agents, enable autofix in the Cursor dashboard.}