cdc: add description about claim-check-raw-value

[3AceShowHand]

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[3AceShowHand]

This feature is planned to be release in v8.4.0

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[LGTM Timeline notifier]

Timeline:

• 2024-09-20 07:50:29.672844786 +0000 UTC m=+1206699.413268725: ☑️ agreed by Oreoxmt.
• 2024-09-23 10:03:05.023986974 +0000 UTC m=+1473854.764410897: ☑️ agreed by qiancai.