refactor: make git package handle all git operations (#38543)

before: gitrepo vs git packages
after: git package fully handle all git operations

by the way, use `WithRepo(repo)` instead of `WithDir(repo.Path)` to hide
path details.

benefits:

1. remove all unnecessary wrappers, developers no need to struggle with
"which package should be used"
2. simplify code, RepositoryFacade can (will) be used everywhere, all
"path" details are (will be) hidden

modules/repository/temp.go

@@ -7,16 +7,18 @@ import (
 	"context"
 	"fmt"
 
-	"gitea.dev/modules/log"
+	"gitea.dev/modules/git"
+	"gitea.dev/modules/git/gitcmd"
 	"gitea.dev/modules/setting"
 )
 
-// CreateTemporaryPath creates a temporary path
-func CreateTemporaryPath(prefix string) (string, context.CancelFunc, error) {
-	basePath, cleanup, err := setting.AppDataTempDir("local-repo").MkdirTempRandom(prefix + ".git")
+// CreateTemporaryGitRepo creates a temporary Git repository empty directory (not initialized)
+func CreateTemporaryGitRepo(prefix string) (tmpPath string, tmpRepo git.RepositoryFacade, cancel context.CancelFunc, err error) {
+	tmpNamePrefix := prefix + ".git"
+	tmpPath, cancel, err = setting.AppDataTempDir("local-repo").MkdirTempRandom(tmpNamePrefix)
 	if err != nil {
-		log.Error("Unable to create temporary directory: %s-*.git (%v)", prefix, err)
-		return "", nil, fmt.Errorf("failed to create dir %s-*.git: %w", prefix, err)
+		return "", nil, nil, fmt.Errorf("failed to create temp dir with prefix %s: %w", tmpNamePrefix, err)
 	}
-	return basePath, cleanup, nil
+	tmpRepo = gitcmd.RepositoryUnmanaged(tmpPath)
+	return tmpPath, tmpRepo, cancel, nil
 }