add port and schema to federation host (#7203)

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### Tests

- I added test coverage for Go changes...
  - [x] in their respective `*_test.go` for unit tests.
  - [ ] in the `tests/integration` directory if it involves interactions with a live Forgejo server.

### Documentation

- [ ] I created a pull request [to the documentation](https://codeberg.org/forgejo/docs) to explain to Forgejo users how to use this change.
- [ ] I did not document these changes and I do not expect someone else to do it.

### Release notes

- [ ] I do not want this change to show in the release notes.
- [ ] I want the title to show in the release notes with a link to this pull request.
- [ ] I want the content of the `release-notes/<pull request number>.md` to be be used for the release notes instead of the title.

Co-authored-by: Michael Jerger <michael.jerger@meissa-gmbh.de>
Reviewed-on: https://codeberg.org/forgejo/forgejo/pulls/7203
Reviewed-by: Earl Warren <earl-warren@noreply.codeberg.org>
Co-authored-by: zam <mirco.zachmann@meissa.de>
Co-committed-by: zam <mirco.zachmann@meissa.de>

models/user/activitypub.go

@@ -4,13 +4,10 @@
 package user
 
 import (
-	"context"
 	"fmt"
 	"net/url"
 
-	"forgejo.org/models/db"
 	"forgejo.org/modules/setting"
-	"forgejo.org/modules/validation"
 )
 
 // APActorID returns the IRI to the api endpoint of the user
@@ -26,19 +23,3 @@ func (u *User) APActorID() string {
 func (u *User) APActorKeyID() string {
 	return u.APActorID() + "#main-key"
 }
-
-func GetUserByFederatedURI(ctx context.Context, federatedURI string) (*User, error) {
-	user := new(User)
-	has, err := db.GetEngine(ctx).Where("normalized_federated_uri=?", federatedURI).Get(user)
-	if err != nil {
-		return nil, err
-	} else if !has {
-		return nil, nil
-	}
-
-	if res, err := validation.IsValid(*user); !res {
-		return nil, err
-	}
-
-	return user, nil
-}