[Feature Request] Allow hiding of pre-processed device nodes

[Obsessee]

I want to ensure that applications use the processed EasyEffects Sink/Source and cannot access the pre-processed nodes.

It might be possible to use some new features that WirePlumber and PipeWire have been working on to accomodate devices that need DSP before being used. Here is the merge request implementing the hiding of nodes, for reference.

[wwmm]

This feels like something designed for PipeWire's built-in filter chain. It does not seem usable by EasyEffects. Differently from what some users think pipewire's filter chain is useless for easyeffects. Our filters pipeline is handled in a totally different way.

If at the the end of the day the idea is having easyeffects virtual devices as the target device of this new mechanism just disable the automatic redirection of streams in easyeffects preferences window and make wireplumber move the streams to us by itself.