Add some utility functions for creating default messages and action effects.

[AHartNtkn]

A new file is added at node/utils.juvix.md. This contains functions for creating default messages and action effects which follow patterns which have been frequently repeated across engines. Using these, the code for the behavior of several of the engines can be made much shorter and a bit more readable.

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  • Node Architecture Change
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  • Juvix Types/Package Update
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[github-actions]

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