`Denoise Current Render` issues

Tested on `Chunky 2.4.0` with #30

Note, using default 16 SPP for Albedo and Normal maps. Opted to write this SPP as a number opposed to a variable to ease confusion.

Upon using `Denoise Current Render`:

- If the current beauty pass SPP is 0 & albedo+normal are disabled - Renderer breaks at `0 of 16` ETA: Somelargenumber. Beauty pass SPP is also set to 16 SPP internally and the field needs to be refreshed. `Advanced Tab` `Renderer` is not updated and still shows `PathTracingRenderer`. Upon toggling/updating this tab it will show the actual Renderer as being `DenoiserPasses`.
- If the current beauty pass SPP is 0 & albedo+normal are enabled - Only the Albedo is rendered and it is rendered to 16 SPP. Saved as `-spp.png`? This is the default snapshot format? Beauty pass SPP is also set to 16 SPP internally and the field needs to be refreshed. Same as the `Renderer` in the `Advanced Tab`.
- If the current beauty pass SPP is at N & albedo+normal are disabled - Renderer breaks at `0 of 16` ETA: Somelargenumber. See above.
- If the current beauty pass SPP is at N & albedo and/or normal are enabled - We get the (noisy) beauty pass saved at N spp at a certain time. We also get a denoised beauty pass at 16 SPP 20 minutes "before" the (noisy) beauty pass was made. eg- beauty pass completed 21:17. Denoised 20:57. -- This behaviour is repeatable. Beauty pass SPP is also set to 16 SPP internally and the field needs to be refreshed; Same as the `Renderer` in the `Advanced Tab`.

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Key Issues:

1) If the albedo and normal are disabled `Denoise Current Render` does not function correctly. We do not need any feature/auxiliary images to use OIDN.
2) Selected `Renderer` is changed to `DenoiserPasses` but UI does not always reflect this and needs to be refreshed.
a) Ideally the Renderer should default back to the original Renderer after the operation has completed.
3) The Beauty pass Target SPP is set to match the Albedo/Normal map SPP (I assume it is the last one) and the UI does not reflect this and needs to be refreshed.
4) Outputted (denoised) files lack any suffixes to identify them under

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Extended issues:

This button does not address similar issues ( #13 #15 #27 ) and is regarded to be highly destructive to in progress renders and will overwrite render dumps. If the button is to be kept in it's current form we will need to implement a warning.