remove dead split_labels helper

Its only caller was the deleted yoloworld_onnx.cc.

AGENTS.md

@@ -34,7 +34,7 @@ Camera and detection behavior is configured entirely through environment variabl
 - **`src/zed/camera.cc`** — Implementation. SDK enum parsers live in an anonymous namespace.
 - **`src/engines/engine.h`** — `engines::DetectedObject` struct and `engines::Engine` abstract base class (`enable`, `detect`, `objects`, `label_names`).
 - **`src/engines/zed_native.h/cc`** — `engines::ZedNative`: wraps ZED SDK's TensorRT-optimized object detection module.
-- **`src/engines/yolo_helpers.h`** — Header-only shared helpers used by the ONNX engine: `RawDetection`, `nms()`, `letterbox()`, `fuse_bbox()`, `backproject()`, `split_labels()`. Lives in `engines::detail` namespace.
+- **`src/engines/yolo_helpers.h`** — Header-only shared helpers used by the ONNX engine: `RawDetection`, `nms()`, `letterbox()`, `fuse_bbox()`, `backproject()`. Lives in `engines::detail` namespace.
 - **`src/engines/yolo_onnx.h/cc`** — `engines::YoloOnnx` / `YoloOnnxConfig`: closed-vocabulary detection for any single-input YOLO ONNX model (YOLOv8, YOLOv11, YOLOv5, etc.). Auto-detects output layout (`NC_FIRST` / `NC_LAST` / `NC_LAST_OBJ`) from tensor shape; override with `ZED_ONNX_OUTPUT_FORMAT`. Labels loaded from `ZED_ONNX_LABELS` or `ZED_ONNX_LABELS_FILE`.
 - **`src/main.cc`** — Dora event loop. Selects engine via `ZED_ENGINE` env var (`yolo_onnx`/`onnx` or `native`), holds a `std::unique_ptr<engines::Engine>`. Parses `ZED_PC_MODE` (`FULL`/`HALF`/`ROI`) once before the loop. On `tick` input: calls `camera.grab()` and `detector->detect()`, then sends `image_bgr`, `point_cloud`, `camera_info`, and `objects` outputs. Point cloud output varies by mode: `FULL` sends the raw `sl::Mat` pointer (no copy); `HALF` downsamples by 2 in each dimension; `ROI` emits only valid points within detected bounding boxes as a flat `[N, 4]` array. Handles reconnection on grab failure.
 - **`DoraTargets.cmake`** — Handles building or fetching dora-rs and generating the CXX bridge files. Two paths: local (`DORA_ROOT_DIR`) or git clone. Produces `dora_node_api_cxx` library and the `node_bridge.cc` glue.

src/engines/yolo_helpers.h

@@ -5,8 +5,6 @@
 
 #include <algorithm>
 #include <cmath>
-#include <sstream>
-#include <string>
 #include <vector>
 
 namespace engines::detail {
@@ -135,19 +133,4 @@ inline void backproject(float u, float v, float z,
     Y = (v - cy) * z / fy;
 }
 
-// --- Label parsing ---
-
-inline std::vector<std::string> split_labels(const std::string& s) {
-    std::vector<std::string> out;
-    std::stringstream ss(s);
-    std::string tok;
-    while (std::getline(ss, tok, ',')) {
-        size_t l = tok.find_first_not_of(" \t");
-        size_t r = tok.find_last_not_of(" \t");
-        if (l != std::string::npos)
-            out.push_back(tok.substr(l, r - l + 1));
-    }
-    return out;
-}
-
 } // namespace engines::detail