* add themes from https://github.com/eza-community/eza-themes
* init eza theme during install
* add migration
* refactor migration script to only link eza theme if it exists for current theme
* only link to eza theme if current theme supports it
* only link to eza theme if current theme supports it
* Cleanup
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Co-authored-by: David Heinemeier Hansson <david@hey.com>