Fixes #17453 This PR adds the abbility to block a user from a personal account or organization to restrict how the blocked user can interact with the blocker. The docs explain what's the consequence of blocking a user. Screenshots: ![grafik](https://github.com/go-gitea/gitea/assets/1666336/4ed884f3-e06a-4862-afd3-3b8aa2488dc6) ![grafik](https://github.com/go-gitea/gitea/assets/1666336/ae6d4981-f252-4f50-a429-04f0f9f1cdf1) ![grafik](https://github.com/go-gitea/gitea/assets/1666336/ca153599-5b0f-4b4a-90fe-18bdfd6f0b6b) --------- Co-authored-by: Lauris BH <lauris@nix.lv>