Modernized IDE interface and appearance controls

The OL Code interface now uses the OpenLegacy kit components across dialogs, buttons, tables, menus, forms, toasts, and navigation. The explorer and editor received colored icons, a cleaner search row, collapse-all support, side-by-side diffs, a scale picker, and look controls in the user menu. See [[feature:legacy-explorer-code-editor|Legacy explorer and code editor]] for the editor workspace capability.