feat: txn limit shift to 1TB

[Icemap]

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[ti-chi-bot[bot]]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: Once this PR has been reviewed and has the lgtm label, please assign ran-huang for approval. For more information see the Kubernetes Code Review Process.

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[Icemap]

/cc @Oreoxmt

[Oreoxmt]

@you06 Could you please help review this?

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[qiancai]

Removed the needs-cherry-pick-release-7.3 label because the v7.3 docs have been archived at https://docs-archive.pingcap.com/zh/tidb/v7.3 and will no longer receive new updates

[qiancai]

Removed the needs-cherry-pick-release-7.4 label because the v7.4 docs have been archived at https://docs-archive.pingcap.com/zh/tidb/v7.4 and will no longer receive new updates.

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