feat(akita-field): add serde to akita-field - #400

Bugbot Analysis Progress (2m 41s elapsed)

✅ Gathered PR context (5s)
✅ Completed bug detection (2m 35s)
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Final Result: Bugbot completed review - no issues found! ✅

Request ID: serverGenReqId_8462b559-79ef-42b2-80fc-b1977dd2e8d0