docs(nix): remove premature forwarding rule

docs/nix.md

@@ -129,26 +129,6 @@ Use:
 }:
 ```
 
-### Use `@` for forwarding wrappers
-
-Use `@` when a wrapper passes its complete argument set to another function.
-Name each argument the wrapper uses before `...`.
-Forward the bound argument set unchanged.
-
-Avoid:
-
-```nix
-{ hostName, system ? "x86_64-linux", ... }:
-mkHost { inherit hostName system; }
-```
-
-Use:
-
-```nix
-args@{ hostName, ... }:
-mkHost args
-```
-
 ## `let` Bindings
 
 ### Use `let` for named intermediate values