refactor!: remove parser structs from `ColumnOperationError`

[iajoiner]

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Rationale for this change

This change is made to simplify column operations partly in order to simplify owned_column_operation.rs and partly in preparation for the new version of provable arithmetic expressions.

What changes are included in this PR?

• replace BinaryOp and UnaryOp in ColumnOperationError with strings

  Existing tests should pass

[github-actions[bot]]

:tada: This PR is included in version 0.40.0 :tada:

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