Fix build errors: FTPS AsyncRead bridge, TLS connector type, unsafe env::set_var, dead code

Verified with cargo check + cargo run --example printer_polymorphism.

src/printer/klipper.rs

@@ -1,3 +1,5 @@
+use std::time::Duration;
+
 use tracing::info;
 
 use super::{Printer, PrinterBase, PrinterError};
@@ -27,7 +29,10 @@ impl Printer for KlipperPrinter {
     async fn connect(&mut self) -> Result<(), PrinterError> {
         info!(printer = %self.base.id, host = %self.base.host, "probing Moonraker over HTTP");
 
-        reqwest::get(format!("http://{}/printer/info", self.base.host))
+        reqwest::Client::new()
+            .get(format!("http://{}/printer/info", self.base.host))
+            .timeout(Duration::from_secs(5))
+            .send()
             .await
             .and_then(|resp| resp.error_for_status())
             .map_err(|err| PrinterError::Connection(self.base.id.clone(), err.to_string()))?;