feat: Follow remote users; feed tab (#10380)

This is hopefully the final part of PR #4767, rebased and squashed.

More thorough federation tests are at https://code.forgejo.org/forgejo/end-to-end/pulls/1276 but the mock has been extended to hopefully cover a good chunk as well.

Co-authored-by: Gergely Nagy <forgejo@gergo.csillger.hu>
Co-authored-by: Michael Jerger <michael.jerger@meissa-gmbh.de>
Co-authored-by: zam <mirco.zachmann@meissa.de>
Co-authored-by: Panagiotis "Ivory" Vasilopoulos <git@n0toose.net>

Reviewed-on: https://codeberg.org/forgejo/forgejo/pulls/10380
Reviewed-by: Gusted <gusted@noreply.codeberg.org>
Co-authored-by: famfo <famfo@famfo.xyz>
Co-committed-by: famfo <famfo@famfo.xyz>

models/activities/federated_user_activity.go

@@ -82,7 +82,7 @@ func GetFollowingFeeds(ctx context.Context, actorID int64, opts GetFollowingFeed
 	sess = db.SetSessionPagination(sess, &opts)
 
 	actions := make([]*FederatedUserActivity, 0, opts.PageSize)
-	count, err := sess.FindAndCount(&actions)
+	count, err := sess.Desc("`federated_user_activity`.created").FindAndCount(&actions)
 	if err != nil {
 		return nil, 0, fmt.Errorf("FindAndCount: %w", err)
 	}

models/user/federated_user.go

@@ -5,6 +5,7 @@ package user
 
 import (
 	"database/sql"
+	"fmt"
 
 	"forgejo.org/modules/validation"
 )
@@ -42,3 +43,18 @@ func (federatedUser FederatedUser) Validate() []string {
 	result = append(result, validation.ValidateNotEmpty(federatedUser.InboxPath, "InboxPath")...)
 	return result
 }
+
+func (federatedUser *FederatedUser) LogString() string {
+	if federatedUser == nil {
+		return "<FederatedUser nil>"
+	}
+
+	return fmt.Sprintf(
+		"<FederatedUser ID: %d, UserID: %d, ExternalID: %s, NormalizedOriginalURL: %s, InboxPath: %s>",
+		federatedUser.ID,
+		federatedUser.UserID,
+		federatedUser.ExternalID,
+		federatedUser.NormalizedOriginalURL,
+		federatedUser.InboxPath,
+	)
+}