[MODERATION] user blocking

- Add the ability to block a user via their profile page.
- This will unstar their repositories and visa versa.
- Blocked users cannot create issues or pull requests on your the doer's repositories (mind that this is not the case for organizations).
- Blocked users cannot comment on the doer's opened issues or pull requests.
- Blocked users cannot add reactions to doer's comments.
- Blocked users cannot cause a notification trough mentioning the doer.

Reviewed-on: https://codeberg.org/forgejo/forgejo/pulls/540
(cherry picked from commit 687d852480)
(cherry picked from commit 0c32a4fde5)

routers/web/web.go

@@ -520,6 +520,8 @@ func registerRoutes(m *web.Route) {
 			})
 			addWebhookEditRoutes()
 		}, webhooksEnabled)
+
+		m.Get("/blocked_users", user_setting.BlockedUsers)
 	}, reqSignIn, ctxDataSet("PageIsUserSettings", true, "AllThemes", setting.UI.Themes, "EnablePackages", setting.Packages.Enabled))
 
 	m.Group("/user", func() {