refactor: Isolate arrow code #237

[melsonic]

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Rationale for this change

Currently, arrow is one of the elements that must be disabled to enable no_std support. Additionally, not every use-case requires arrow. So, it is gated behind a features flag (feature = "arrow"). However, there are many instances of #[cfg(feature = "arrow")] throughout the codebase, which leaves the code cluttered.

What changes are included in this PR?

This PR isolates the code using arrow into a separate module.

TODO

Only the documentation part is left, which I will do in the next commit, other than that the code is working fine.

/claim #237