Proxy envs need to get elevated (#342)

src/cli/mod.rs

@@ -107,6 +107,8 @@ pub fn ensure_root() -> eyre::Result<()> {
                 "GITHUB_PATH" => true,
                 // Used for detecting what command to suggest for sourcing Nix
                 "SHELL" => true,
+                // Proxy settings (automatically picked up by Reqwest)
+                "HTTP_PROXY" | "http_proxy" | "HTTPS_PROXY" | "https_proxy" => true,
                 // Our own environments
                 key if key.starts_with("NIX_INSTALLER") => true,
                 _ => false,