fix(hu): address Copilot round-2 findings on PR #236

- ros.rs: use checked integer conversions (try_from) for JSON->CDR so
  out-of-range values error instead of silently truncating
- state.rs: reject window_ms == 0 in get_tracker_snapshot to avoid
  divide-by-zero producing inf/NaN rates in measure_hz/measure_bw
- engine.rs: serialize connect/endpoints with serde_json instead of
  format! to be safe against quotes/backslashes in router addresses
- mod.rs: strip both hu- and hu_ prefixes for plugin work-dir naming,
  matching discover_wasm_plugins

Author: YuanYuYuan

crates/hiroz-union/src/core/engine.rs

@@ -71,7 +71,9 @@ impl CoreEngine {
         // are long-lived, so the startup cost is invisible to them.)
         let mut config = zenoh::Config::default();
         config.insert_json5("mode", "\"client\"")?;
-        config.insert_json5("connect/endpoints", &format!("[\"{}\"]", router_addr))?;
+        let endpoints_json = serde_json::to_string(&[router_addr])
+            .map_err(|e| format!("failed to serialize router endpoint: {e}"))?;
+        config.insert_json5("connect/endpoints", &endpoints_json)?;
         config.insert_json5("scouting/multicast/enabled", "false")?;
 
         let session = zenoh::open(config.clone()).await.map_err(|e| {

crates/hiroz-union/src/plugin/wasm/host/ros.rs

@@ -409,23 +409,29 @@ fn json_to_dynamic_value(
     match ty {
         FieldType::Bool => Ok(DynamicValue::Bool(value.as_bool().ok_or("expected bool")?)),
         FieldType::Int8 => Ok(DynamicValue::Int8(
-            value.as_i64().ok_or("expected i8")? as i8
+            i8::try_from(value.as_i64().ok_or("expected i8")?)
+                .map_err(|_| "value out of range for i8")?,
         )),
         FieldType::Int16 => Ok(DynamicValue::Int16(
-            value.as_i64().ok_or("expected i16")? as i16
+            i16::try_from(value.as_i64().ok_or("expected i16")?)
+                .map_err(|_| "value out of range for i16")?,
         )),
         FieldType::Int32 => Ok(DynamicValue::Int32(
-            value.as_i64().ok_or("expected i32")? as i32
+            i32::try_from(value.as_i64().ok_or("expected i32")?)
+                .map_err(|_| "value out of range for i32")?,
         )),
         FieldType::Int64 => Ok(DynamicValue::Int64(value.as_i64().ok_or("expected i64")?)),
         FieldType::Uint8 => Ok(DynamicValue::Uint8(
-            value.as_u64().ok_or("expected u8")? as u8
+            u8::try_from(value.as_u64().ok_or("expected u8")?)
+                .map_err(|_| "value out of range for u8")?,
         )),
         FieldType::Uint16 => Ok(DynamicValue::Uint16(
-            value.as_u64().ok_or("expected u16")? as u16
+            u16::try_from(value.as_u64().ok_or("expected u16")?)
+                .map_err(|_| "value out of range for u16")?,
         )),
         FieldType::Uint32 => Ok(DynamicValue::Uint32(
-            value.as_u64().ok_or("expected u32")? as u32
+            u32::try_from(value.as_u64().ok_or("expected u32")?)
+                .map_err(|_| "value out of range for u32")?,
         )),
         FieldType::Uint64 => Ok(DynamicValue::Uint64(value.as_u64().ok_or("expected u64")?)),
         FieldType::Float32 => Ok(DynamicValue::Float32(

crates/hiroz-union/src/plugin/wasm/mod.rs

@@ -431,7 +431,12 @@ fn load_one(
         .file_stem()
         .and_then(|s| s.to_str())
         .unwrap_or("unknown");
-    let plugin_stem = plugin_stem.strip_prefix("hu-").unwrap_or(plugin_stem);
+    // Discovery accepts both `hu-` and `hu_` filename prefixes, so strip either
+    // to keep `hu-meter.wasm` and `hu_meter.wasm` mapping to the same work dir.
+    let plugin_stem = plugin_stem
+        .strip_prefix("hu-")
+        .or_else(|| plugin_stem.strip_prefix("hu_"))
+        .unwrap_or(plugin_stem);
     let work_dir = plugin_work_dir(plugin_stem);
     std::fs::create_dir_all(&work_dir).ok();
 

crates/hiroz-union/src/plugin/wasm/state.rs

@@ -211,6 +211,9 @@ impl PluginState {
         window_ms: u32,
     ) -> Result<(usize, usize, f64), String> {
         self.require_perm(hu::plugin::types::Permission::MeasureMetrics)?;
+        if window_ms == 0 {
+            return Err("window_ms must be greater than zero".to_string());
+        }
         self.ensure_rate_tracker(topic)?;
         let tracker = self.rate_trackers.get_mut(topic).unwrap();
         tracker.drain_and_trim(window_ms);