feat: add sepia effect

[damienmontastier]

This component introduces the Sepia effect, which provides an abstraction for applying a sepia effect, giving a vintage look to the scene. The <SepiaPmndrs> effect is specifically designed to add dynamic and immersive visual effects by altering the colors of the scene, enhancing artistic quality and realism.

• Easy to set up — simply include it in your <EffectComposerPmndrs> pipeline.
• Multiple options for controlling the intensity of the effect are available.
• Fully supports different blend functions for enhanced customization.

For more details, see SepiaEffect on pmndrs/postprocessing.

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