[Feature]: Create a spectral join function which allows left right inner or other joins between two spectral datasets

[wincowgerDEV]

Guidelines

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Description

I think having different ways to join spectra besides just c_spec would be really nice.

Problem

C_spec is basically an rbind. We don't currently have a way to do anything like an inner or outer join based on metadata fields. Would want to avoid duplication.

Proposed Solution

Not sure the best way to do this yet, still conceptual.

Alternatives Considered

People can find index values needed and pass through filter_spec and c_spec to do something similar.