feat: add `base::database::ColumnarValue`

[iajoiner]

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Rationale for this change

We need to add ColumnarValue so that we can remove table_length from ProofExpr::result_evaluate which helps with ProofPlan composition.

What changes are included in this PR?

• add base::database::ColumnarValue

  Yes

[iajoiner]

Just rebasing. No changes since @JayWhite2357 's last approval.

[github-actions[bot]]

:tada: This PR is included in version 0.35.2 :tada:

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