Add disable download source configuration (#20548) (#20579)

* Add disable download source configuration (#20548)

Add configuration to enable/disable download source from UI.

Co-authored-by: zeripath <art27@cantab.net>

* Fix BaseVars not used in renderering

* Fix disabled open in vscode menu when disabling download source from UI

Co-authored-by: zeripath <art27@cantab.net>
Co-authored-by: Lauris BH <lauris@nix.lv>

modules/setting/repository.go

@@ -48,6 +48,7 @@ var (
 		DefaultBranch                           string
 		AllowAdoptionOfUnadoptedRepositories    bool
 		AllowDeleteOfUnadoptedRepositories      bool
+		DisableDownloadSourceArchives           bool
 
 		// Repository editor settings
 		Editor struct {