[wallyxjh]

Summary

• restore PolarDB-X DN replica controls in the edit UI and allow v1/v2alpha resource update APIs to generate HorizontalScaling OpsRequests for dn-0
• retain omitted-replica protection, odd replica validation, and prior PolarDB-X resource, history, restart, and storage-allocation fixes
• remove the temporary UI/API validation block and its disabled-state copy
• retain Helm runtime environment injection fixes included by the preceding migration commit

Verification

• npx --no-install tsx --test __tests__/unit/services/polardbx-update.test.ts __tests__/unit/utils/polardbx.test.ts from release-v5.1/database (16 passed)
• helm lint release-v5.1/database/deploy/charts/database-frontend
• python3 -m unittest tests.test_deployment_compatibility (4 passed)
• built linux/amd64 image and deployed sealos.hub:5000/labring/sealos-dbprovider-frontend:polardbx-replica-scaling-restore-20261020 to 192.168.128.241; rollout is Ready with image digest sha256:55684c84e9f95593cc3ab0b2b227cfcd5b3f7ae8810db11d86089bde562cc230

Risk

This restores request generation only. It does not repair the existing test-db PolarDB-X DN split-brain/multiple-leader state, and a submitted replica-scale request can still expose the addon consensus-member lifecycle defect.