Rework create/fork/adopt/generate repository to make sure resources will be cleanup once failed (#31035)

Fix #28144 

To make the resources will be cleanup once failed. All repository
operations now follow a consistent pattern:

- 1. Create a database record for the repository with the status
being_migrated.
- 2. Register a deferred cleanup function to delete the repository and
its related data if the operation fails.
- 3.	Perform the actual Git and database operations step by step.
- 4. Upon successful completion, update the repository’s status to
ready.

The adopt operation is a special case — if it fails, the repository on
disk should not be deleted.

services/repository/create_test.go

@@ -0,0 +1,57 @@
+// Copyright 2025 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package repository
+
+import (
+	"os"
+	"testing"
+
+	"code.gitea.io/gitea/models/db"
+	repo_model "code.gitea.io/gitea/models/repo"
+	"code.gitea.io/gitea/models/unittest"
+	user_model "code.gitea.io/gitea/models/user"
+	"code.gitea.io/gitea/modules/git"
+	"code.gitea.io/gitea/modules/util"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestCreateRepositoryDirectly(t *testing.T) {
+	assert.NoError(t, unittest.PrepareTestDatabase())
+
+	// a successful creating repository
+	user2 := unittest.AssertExistsAndLoadBean(t, &user_model.User{ID: 2})
+
+	createdRepo, err := CreateRepositoryDirectly(git.DefaultContext, user2, user2, CreateRepoOptions{
+		Name: "created-repo",
+	})
+	assert.NoError(t, err)
+	assert.NotNil(t, createdRepo)
+
+	exist, err := util.IsExist(repo_model.RepoPath(user2.Name, createdRepo.Name))
+	assert.NoError(t, err)
+	assert.True(t, exist)
+
+	unittest.AssertExistsAndLoadBean(t, &repo_model.Repository{OwnerName: user2.Name, Name: createdRepo.Name})
+
+	err = DeleteRepositoryDirectly(db.DefaultContext, user2, createdRepo.ID)
+	assert.NoError(t, err)
+
+	// a failed creating because some mock data
+	// create the repository directory so that the creation will fail after database record created.
+	assert.NoError(t, os.MkdirAll(repo_model.RepoPath(user2.Name, createdRepo.Name), os.ModePerm))
+
+	createdRepo2, err := CreateRepositoryDirectly(db.DefaultContext, user2, user2, CreateRepoOptions{
+		Name: "created-repo",
+	})
+	assert.Nil(t, createdRepo2)
+	assert.Error(t, err)
+
+	// assert the cleanup is successful
+	unittest.AssertNotExistsBean(t, &repo_model.Repository{OwnerName: user2.Name, Name: createdRepo.Name})
+
+	exist, err = util.IsExist(repo_model.RepoPath(user2.Name, createdRepo.Name))
+	assert.NoError(t, err)
+	assert.False(t, exist)
+}