add open-vocab YOLO-World engine with CLIP text encoder

- Add OpenVocab engine: YOLO-World ONNX detection with runtime
  vocabulary via CLIP text embeddings (two-input model support)
- Add header-only C++ CLIP BPE tokenizer (no external deps)
- Add detect(cv::Mat) overload to OpenVocab for camera-free testing
- Add standalone test binary (test_open_vocab) using test/assets images
- Add export scripts for YOLO-World and CLIP text encoder (uv/PEP 723)
- Add installation scripts for Linux x64, ARM (Jetson), and Windows
- Update CMakeLists to use find_package(onnxruntime) instead of FetchContent
- Update README and AGENTS with env vars, setup workflow, and test usage

CMakeLists.txt

@@ -13,10 +13,20 @@ find_package(zed REQUIRED)
 
 find_package(OpenCV REQUIRED)
 
+find_package(onnxruntime REQUIRED)
+set(ONNXRUNTIME_INCLUDE_DIRS "")  # propagated via imported target
+set(ONNXRUNTIME_LIBRARIES onnxruntime::onnxruntime)
+
 link_directories(${dora_link_dirs})
 link_directories(${ZED_LIBRARY_DIR})
 
-add_executable(dora_zed src/main.cc src/zed/camera.cc src/engines/zed_native.cc ${node_bridge})
+add_executable(dora_zed
+    src/main.cc
+    src/zed/camera.cc
+    src/engines/zed_native.cc
+    src/engines/open_vocab.cc
+    ${node_bridge}
+)
 add_dependencies(dora_zed Dora_cxx)
 
 target_include_directories(
@@ -28,8 +38,28 @@ target_include_directories(
         ${ZED_INCLUDE_DIRS}
         ${OpenCV_INCLUDE_DIRS}
         ${CUDAToolkit_INCLUDE_DIRS}
+        ${ONNXRUNTIME_INCLUDE_DIRS}
 )
 
-target_link_libraries(dora_zed dora_node_api_cxx ${ZED_LIBRARIES} ${OpenCV_LIBS})
+target_link_libraries(dora_zed dora_node_api_cxx ${ZED_LIBRARIES} ${OpenCV_LIBS} ${ONNXRUNTIME_LIBRARIES})
 
 install(TARGETS dora_zed DESTINATION ${CMAKE_CURRENT_SOURCE_DIR}/bin)
+
+# Standalone detector test — no dora, no live camera required
+add_executable(test_open_vocab
+    src/test_open_vocab.cc
+    src/engines/open_vocab.cc
+)
+target_include_directories(test_open_vocab PRIVATE
+    ${CMAKE_CURRENT_SOURCE_DIR}/src
+    ${ZED_INCLUDE_DIRS}
+    ${OpenCV_INCLUDE_DIRS}
+    ${CUDAToolkit_INCLUDE_DIRS}
+    ${ONNXRUNTIME_INCLUDE_DIRS}
+)
+target_link_libraries(test_open_vocab PRIVATE
+    ${ZED_LIBRARIES}
+    ${OpenCV_LIBS}
+    ${ONNXRUNTIME_LIBRARIES}
+)
+install(TARGETS test_open_vocab DESTINATION ${CMAKE_CURRENT_SOURCE_DIR}/bin)