Removed references to deleted methods EditableImage:WritePixels and EditableImage:ReadPixels and rewrote select descriptions accordingly.

[Finchasaurus]

Changes

Removed references to EditableImage:WritePixels and EditableImage:ReadPixels from the documentation of EditableImage:WritePixelsBuffer and EditableImage:ReadPixelsBuffer, as these methods were removed from the API.
This update ensures that references to non-existent methods do not mislead developers. Additionally, it improves documentation clarity by updating previously outdated descriptions on references to outdated methods.

Devforum update post detailing the removal of EditableImage:WritePixels and EditableImage:ReadPixels among other things.
https://devforum.roblox.com/t/studio-beta-major-updates-to-in-experience-mesh-image-apis/3225681

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