example: write our own customized router using the high-level API which gives access to the correct context and routes

Former-commit-id: d2369c20490619cad0dd6f7b6ed01cdbef51a853

_examples/routing/custom-low-level-router/main.go

@@ -0,0 +1,6 @@
+/// TODO: showcase the `app.Downgrade` feature tomorrow if not already existing elsewhere.
+package main
+
+func main() {
+	panic("TODO")
+}