New `PipeOpEncodePL` for Piecewise Linear Encoding#861

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+1,494-21

Commits on Jan 19, 2025

WIP split PipeOpEncodePL into two PipeOps, one for each method
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Commits on Jan 21, 2025

tiny changes
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Commits on Jan 22, 2025

docs for PipeOpEncodePL + document()
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Commits on Jan 23, 2025

Commits on Jan 28, 2025