Inkplate 6Color Support

**Describe the problem you have/What new integration you would like**

I would like support for the Inkplate 6Color's display. It seems largely similar to the Inkplate 6 and 10 which are already supported but supports 7 colors and only 600x448.

**Please describe your use case for this integration and alternatives you've tried:**

It would be nice to be able to use my color display in addition to the other Inkplate line products.

**Additional context**

https://www.crowdsupply.com/soldered/inkplate-6color

Start by reviewing the existing Inkplate 6 and Inkplate 10 support in the ESPHome codebase, then compare their hardware assumptions with the Inkplate 6Color documentation at the linked product page. Done means the display is supported with its 7 colors and 600x448 resolution, with coverage for the relevant behavior established in the project's existing tests.

Written by the indexing model from the issue text.