Set poster from `ComicInfo.xml` metadata rather than first page

[BaccanoMob]

Describe your suggested feature

The title page are most ideal for poster/preview for the book. For Oneshots or some manga chapters the title page are at a few pages from start.

By default, the first pages is used, and currently it is possible to set it manually via UI or have a copy of the page with the same title as book (loading from local artwork assets). It would be nice if it could be loaded automatically when refreshing metadata or importing itself.

Preferably, get the page from Pages / ComicPageInfo with type FrontCover. Or InnerCover if FrontCover is not specified. And ultimately the first page if none are set.

Alternatively, you could use new attribute Poster as a bool/int to preload the pages as poster/artwork but I feel FrontCover and InnerCover is more than enough to auto set poster.

Other details

No response

Acknowledgements

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[BaccanoMob]

Some additional info:

I mostly prefer to the thumbnails to be as small as possible.

Apparently, autogenerate thumbnail has the lowest size. So it would be ideal for users who has a large library and want to conserve storage.

left -> [largest] local artwork asset (first page) (current quick workaround) center -> [smallest] autogenerated based on first page right -> user uploaded (selected first page via UI)