fix: persist mirror repository metadata (#37519)

The migration repository model now carries Website alongside Description, the GitHub/Gitea downloaders populate it, and mirror finalization persists both description and website so the About section is not empty after creating a mirror.

Fixes #37495

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Signed-off-by: cyphercodes <cyphercodes@users.noreply.github.com>
Co-authored-by: cyphercodes <cyphercodes@users.noreply.github.com>
Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>

modules/migration/repo.go

@@ -11,6 +11,7 @@ type Repository struct {
 	IsPrivate     bool `yaml:"is_private"`
 	IsMirror      bool `yaml:"is_mirror"`
 	Description   string
+	Website       string
 	CloneURL      string `yaml:"clone_url"` // SECURITY: This must be checked to ensure that is safe to be used
 	OriginalURL   string `yaml:"original_url"`
 	DefaultBranch string