chore(pipeline): address review \u2014 release profile, unused deps/methods, docs

Address szegedi's review on the wasm binding:
- Restore the release profile to strip=true and drop debug=true (a debugging
  leftover; matters for the published package size, and matches main).
- Remove the unused @napi-rs/cli runtime dependency \u2014 nothing invokes it and
  main builds the native prebuilds without it.
- Remove the unused StatsCollector::flush and set_agent_url methods (dead since
  flush was split into prepare_request/send_request); clears the dead_code warning.
- Fix the prepareChunk error message (was mislabeled sendPreparedChunk) and the
  parse_response_headers doc (it takes a flat [name, value, ...] array, not an
  object).
- Document why the WASM_MEMORY LazyLock<JsValue> is Sync (wasm32-only).

Author: bengl

Cargo.toml

@@ -13,5 +13,4 @@ codegen-units = 1
 lto = true
 opt-level = "z"
 panic = "abort"
-# strip = "none"
-debug = true
+strip = true

crates/capabilities/src/http.rs

@@ -19,6 +19,9 @@ use wasm_bindgen_futures::JsFuture;
 use libdd_capabilities::http::{HttpClientCapability, HttpError};
 use libdd_capabilities::maybe_send::MaybeSend;
 
+// A `static` requires `Sync`, and `LazyLock<JsValue>: Sync` needs `JsValue:
+// Sync` — which holds only because on wasm32 (single-threaded) wasm-bindgen
+// implements `Send`/`Sync` for `JsValue`. This crate is wasm32-only, so it's sound.
 static WASM_MEMORY: LazyLock<JsValue> = LazyLock::new(wasm_bindgen::memory);
 
 #[wasm_bindgen(module = "/src/http_transport.js")]
@@ -132,9 +135,9 @@ impl HttpClientCapability for WasmHttpClient {
     }
 }
 
-/// Parse response headers from a JS object `{ "header-name": "value", ... }`.
-///
-/// Node.js `res.headers` returns lowercased header names with string values.
+/// Parse response headers from Node's flat `[name, value, name, value, ...]`
+/// array (`res.rawHeaders`): even indices are (lowercased) header names, odd
+/// indices their string values.
 fn parse_response_headers(header_js: Array<JsString>) -> Result<HeaderMap, HttpError> {
     let len = header_js.length() as usize;
     let mut headers = HeaderMap::with_capacity(len / 2);

crates/pipeline/src/lib.rs

@@ -405,7 +405,7 @@ impl WasmSpanState {
         let mut span_ids = Vec::with_capacity(count as usize);
         while count > 0 {
             let span_id: u64 = get_num(chunk, &mut index)
-                .ok_or_else(|| JsValue::from_str("sendPreparedChunk: span id index out of bounds"))?;
+                .ok_or_else(|| JsValue::from_str("prepareChunk: span id index out of bounds"))?;
             span_ids.push(span_id);
             count -= 1;
         }

crates/pipeline/src/stats.rs

@@ -123,28 +123,6 @@ impl StatsCollector {
             .map_err(|e| format!("stats send error: {e:?}"))?;
         Ok(())
     }
-
-    /// Flush aggregated stats and send to the agent.
-    ///
-    /// Returns `Ok(true)` if stats were sent, `Ok(false)` if there was nothing
-    /// to send, or `Err` on transport failure. Convenience wrapper around
-    /// `prepare_request` + `send_request`; callers that flush concurrently with
-    /// trace export should use those two directly so the collector isn't held
-    /// across the await (see `flushStats`).
-    pub async fn flush(&mut self, force: bool) -> Result<bool, String> {
-        match self.prepare_request(force)? {
-            Some(req) => {
-                Self::send_request(req).await?;
-                Ok(true)
-            }
-            None => Ok(false),
-        }
-    }
-
-    /// Update the agent URL (e.g. after reconfiguration).
-    pub fn set_agent_url(&mut self, url: String) {
-        self.agent_url = url;
-    }
 }
 
 /// Encode flushed stats buckets into a `ClientStatsPayload` for msgpack

package.json

@@ -29,9 +29,6 @@
   "publishConfig": {
     "access": "public"
   },
-  "dependencies": {
-    "@napi-rs/cli": "^3.6.0"
-  },
   "devDependencies": {
     "@eslint/js": "^10.0.1",
     "@stylistic/eslint-plugin": "^5.9.0",