### Is your feature request related to a problem? Please describe.

You can't use channel() on const Magick::Images. This is unfortunate, because a copy of the Magick::Image is needed.

### Describe the solution you'd like

Introduce a getConstChannel() method or a const override for channel()

### Describe alternatives you've considered

A copy of the Magick::Image

### Additional context

_No response_
Magick++: Magick::Image::channel() can not be used on const Magick::Image
This is a GitHub Issue
repo:ImageMagick
owner:ImageMagick
Title : Magick++: Magick::Image::channel() can not be used on const Magick::Image
Issue date:

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### Is your feature request related to a problem? Please describe.

You can't use channel() on const Magick::Images. This is unfortunate, because a copy of the Magick::Image is needed.

### Describe the solution you'd like

Introduce a getConstChannel() method or a const override for channel()

### Describe alternatives you've considered

A copy of the Magick::Image

### Additional context

_No response_
--- end body ---
