Federated user activity following: Isolated model changes (#8078)

This PR is part of https://codeberg.org/forgejo/forgejo/pulls/4767

This should not have an outside impact but bring all model changes needed & bring migrations.

Reviewed-on: https://codeberg.org/forgejo/forgejo/pulls/8078
Reviewed-by: Earl Warren <earl-warren@noreply.codeberg.org>
Co-authored-by: Michael Jerger <michael.jerger@meissa-gmbh.de>
Co-committed-by: Michael Jerger <michael.jerger@meissa-gmbh.de>

models/forgejo_migrations/v33_test.go

@@ -0,0 +1,46 @@
+// Copyright 2025 The Forgejo Authors.
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+package forgejo_migrations //nolint:revive
+
+import (
+	"testing"
+	"time"
+
+	migration_tests "forgejo.org/models/migrations/test"
+	"forgejo.org/modules/log"
+	ft "forgejo.org/modules/test"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func Test_FederatedUserActivityMigration(t *testing.T) {
+	lc, cl := ft.NewLogChecker(log.DEFAULT, log.WARN)
+	lc.Filter("migration[33]")
+	defer cl()
+
+	// intentionally conflicting definition
+	type FederatedUser struct {
+		ID     int64 `xorm:"pk autoincr"`
+		UserID string
+	}
+
+	// Prepare TestEnv
+	x, deferable := migration_tests.PrepareTestEnv(t, 0,
+		new(FederatedUser),
+	)
+	sessTest := x.NewSession()
+	sessTest.Insert(FederatedUser{UserID: "1234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890" +
+		"1234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890" +
+		"1234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890"})
+	sessTest.Commit()
+	defer deferable()
+	if x == nil || t.Failed() {
+		return
+	}
+
+	require.NoError(t, FederatedUserActivityMigration(x))
+	logFiltered, _ := lc.Check(5 * time.Second)
+	assert.NotEmpty(t, logFiltered)
+}