fix(gateway): annotate rng.gen as u8 for Windows inference

Signed-off-by: crimsonsunset <jsangio1@gmail.com>

Author: crimsonsunset

crates/mcpmux-gateway/src/oauth/flow.rs

@@ -187,7 +187,7 @@ impl OAuthFlow {
 fn generate_state() -> String {
     use rand::Rng;
     let mut rng = rand::thread_rng();
-    let bytes: Vec<u8> = (0..16).map(|_| rng.gen()).collect();
+    let bytes: Vec<u8> = (0..16).map(|_| rng.gen::<u8>()).collect();
     use base64::{engine::general_purpose::URL_SAFE_NO_PAD, Engine};
     URL_SAFE_NO_PAD.encode(&bytes)
 }

crates/mcpmux-gateway/src/oauth/pkce.rs

@@ -22,7 +22,7 @@ impl PkceChallenge {
     pub fn generate() -> Self {
         // Generate 32 random bytes for the verifier
         let mut rng = rand::thread_rng();
-        let random_bytes: Vec<u8> = (0..32).map(|_| rng.gen()).collect();
+        let random_bytes: Vec<u8> = (0..32).map(|_| rng.gen::<u8>()).collect();
 
         // Base64-URL encode to create verifier (43-128 characters)
         let verifier = URL_SAFE_NO_PAD.encode(&random_bytes);