Tag-related requests

Hi.

I will send you a tag-related proposal.

　・Addition of categories (character,concept...) in the filter displayed when searching for tags.

　・Implementation of tag search.

　・Mandatory tagging.

　　　Models of works set to Hidden Tags are often displayed, or the model of the work you are looking for is not tagged, so it will not be found in searches.

　・Unify tags.

　　(e.g. kantai collection, kancolle, kantaicollection → kantai collection)

　　I think the original title is good.

Please consider implementing them.