fix: add native fallback for sheet/controller subpath to fix Select on native

Metro resolves @tamagui/sheet/controller via filesystem (controller/index.cjs)
instead of package exports, which was loading the web CJS version instead of
the native version, causing a SheetControllerContext mismatch between Select
and Sheet components.

code/ui/sheet/controller/index.native.js

@@ -0,0 +1 @@
+Object.assign(module.exports, require('../dist/cjs/controller.native.js'))