Fix self-review findings: overflow safety, config bounds, language matching

- Use saturating_mul for retry delay calculations to prevent integer overflow
- Enforce minimum bounds for adapter timeout (5s) and retry delay (50ms)
- Handle "en-US" style language codes in output language check

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: haasonsaas

src/adapters/common.rs

@@ -47,7 +47,7 @@ where
                 let status = response.status();
                 let body = response.text().await.unwrap_or_default();
                 if is_retryable_status(status) && attempt < max_retries {
-                    sleep(Duration::from_millis(base_delay_ms * (attempt as u64 + 1))).await;
+                    sleep(Duration::from_millis(base_delay_ms.saturating_mul(attempt as u64 + 1))).await;
                     continue;
                 }
 
@@ -62,7 +62,7 @@ where
             }
             Err(err) => {
                 if attempt < max_retries {
-                    sleep(Duration::from_millis(base_delay_ms * (attempt as u64 + 1))).await;
+                    sleep(Duration::from_millis(base_delay_ms.saturating_mul(attempt as u64 + 1))).await;
                     continue;
                 }
                 return Err(err.into());

src/config.rs

@@ -568,7 +568,7 @@ impl Config {
             if timeout == 0 {
                 self.adapter_timeout_secs = None; // use default
             } else {
-                self.adapter_timeout_secs = Some(timeout.min(600));
+                self.adapter_timeout_secs = Some(timeout.clamp(5, 600));
             }
         }
         // Clamp adapter retries (0-10)
@@ -580,7 +580,7 @@ impl Config {
             if delay == 0 {
                 self.adapter_retry_delay_ms = None;
             } else {
-                self.adapter_retry_delay_ms = Some(delay.min(30_000));
+                self.adapter_retry_delay_ms = Some(delay.clamp(50, 30_000));
             }
         }
         // Normalize output language
@@ -1113,6 +1113,26 @@ mod tests {
         assert_eq!(config.output_language, None);
     }
 
+    #[test]
+    fn normalize_adapter_timeout_clamps_minimum() {
+        let mut config = Config {
+            adapter_timeout_secs: Some(2),
+            ..Config::default()
+        };
+        config.normalize();
+        assert_eq!(config.adapter_timeout_secs, Some(5));
+    }
+
+    #[test]
+    fn normalize_adapter_retry_delay_clamps_minimum() {
+        let mut config = Config {
+            adapter_retry_delay_ms: Some(10),
+            ..Config::default()
+        };
+        config.normalize();
+        assert_eq!(config.adapter_retry_delay_ms, Some(50));
+    }
+
     #[test]
     fn normalize_feedback_suppression_zero_resets() {
         let mut config = Config {

src/review/pipeline.rs

@@ -483,7 +483,7 @@ pub fn build_review_guidance(
 
     // Output language directive
     if let Some(ref lang) = config.output_language {
-        if lang != "en" {
+        if lang != "en" && !lang.starts_with("en-") {
             sections.push(format!(
                 "Write all review comments and suggestions in {}.",
                 lang
@@ -938,6 +938,16 @@ mod tests {
         assert!(!guidance.contains("Write all review comments"));
     }
 
+    #[test]
+    fn build_review_guidance_skips_en_us_language() {
+        let config = config::Config {
+            output_language: Some("en-us".to_string()),
+            ..config::Config::default()
+        };
+        let guidance = build_review_guidance(&config, None).unwrap();
+        assert!(!guidance.contains("Write all review comments"));
+    }
+
     #[test]
     fn build_review_guidance_no_fix_suggestions() {
         let config = config::Config {