[AZ-180] Refactor detection event handling and improve SSE support

- Updated the detection image endpoint to require a channel ID for event streaming.
- Introduced a new endpoint for streaming detection events, allowing clients to receive real-time updates.
- Enhanced the internal buffering mechanism for detection events to manage multiple channels.
- Refactored the inference module to support the new event handling structure.

Made-with: Cursor

tests/test_az180_jetson_int8.py

@@ -96,3 +96,149 @@ def test_convert_from_source_uses_fp16_when_no_cache():
     mock_config.set_flag.assert_any_call("FP16")
     int8_calls = [c for c in mock_config.set_flag.call_args_list if c == call("INT8")]
     assert len(int8_calls) == 0
+
+
+@requires_tensorrt
+def test_trt_factory_build_from_source_uses_fp16():
+    # Arrange
+    from engines.engine_factory import TensorRTEngineFactory
+    from engines.tensorrt_engine import TensorRTEngine
+    import engines.tensorrt_engine as trt_mod
+
+    mock_trt, mock_builder, mock_config = _make_mock_trt()
+    factory = TensorRTEngineFactory()
+
+    with patch.object(trt_mod, "trt", mock_trt), \
+         patch.object(TensorRTEngine, "get_gpu_memory_bytes", return_value=4 * 1024**3):
+        # Act
+        engine_bytes, filename = factory.build_from_source(b"onnx", MagicMock(), "models")
+
+    # Assert
+    assert engine_bytes == b"engine_bytes"
+    assert filename is not None
+    int8_calls = [c for c in mock_config.set_flag.call_args_list if c == call("INT8")]
+    assert len(int8_calls) == 0
+
+
+@requires_tensorrt
+def test_jetson_factory_build_from_source_uses_int8_when_cache_available():
+    # Arrange
+    from engines.engine_factory import JetsonTensorRTEngineFactory
+    from engines.tensorrt_engine import TensorRTEngine
+    import engines.tensorrt_engine as trt_mod
+
+    mock_trt, mock_builder, mock_config = _make_mock_trt()
+    factory = JetsonTensorRTEngineFactory()
+    loader = MagicMock()
+    result = MagicMock()
+    result.err = None
+    result.data = b"calib_data"
+    loader.load_big_small_resource.return_value = result
+
+    with patch.object(trt_mod, "trt", mock_trt), \
+         patch.object(TensorRTEngine, "get_gpu_memory_bytes", return_value=4 * 1024**3):
+        # Act
+        engine_bytes, filename = factory.build_from_source(b"onnx", loader, "models")
+
+    # Assert
+    assert engine_bytes == b"engine_bytes"
+    assert "int8" in filename
+    mock_config.set_flag.assert_any_call("INT8")
+
+
+@requires_tensorrt
+def test_jetson_factory_build_from_source_falls_back_to_fp16_when_no_cache():
+    # Arrange
+    from engines.engine_factory import JetsonTensorRTEngineFactory
+    from engines.tensorrt_engine import TensorRTEngine
+    import engines.tensorrt_engine as trt_mod
+
+    mock_trt, mock_builder, mock_config = _make_mock_trt()
+    factory = JetsonTensorRTEngineFactory()
+    loader = MagicMock()
+    result = MagicMock()
+    result.err = "not found"
+    loader.load_big_small_resource.return_value = result
+
+    with patch.object(trt_mod, "trt", mock_trt), \
+         patch.object(TensorRTEngine, "get_gpu_memory_bytes", return_value=4 * 1024**3):
+        # Act
+        engine_bytes, filename = factory.build_from_source(b"onnx", loader, "models")
+
+    # Assert
+    assert engine_bytes == b"engine_bytes"
+    int8_calls = [c for c in mock_config.set_flag.call_args_list if c == call("INT8")]
+    assert len(int8_calls) == 0
+
+
+@requires_tensorrt
+def test_jetson_factory_cleans_up_cache_tempfile_after_build():
+    # Arrange
+    from engines.engine_factory import JetsonTensorRTEngineFactory
+    from engines.tensorrt_engine import TensorRTEngine
+    import engines.tensorrt_engine as trt_mod
+
+    mock_trt, _, _ = _make_mock_trt()
+    factory = JetsonTensorRTEngineFactory()
+    loader = MagicMock()
+    result = MagicMock()
+    result.err = None
+    result.data = b"calib_data"
+    loader.load_big_small_resource.return_value = result
+
+    written_paths = []
+    original_download = factory._download_calib_cache
+
+    def tracking_download(lc, md):
+        path = original_download(lc, md)
+        if path:
+            written_paths.append(path)
+        return path
+
+    with patch.object(trt_mod, "trt", mock_trt), \
+         patch.object(TensorRTEngine, "get_gpu_memory_bytes", return_value=4 * 1024**3), \
+         patch.object(factory, "_download_calib_cache", side_effect=tracking_download):
+        factory.build_from_source(b"onnx", loader, "models")
+
+    # Assert: temp file was deleted after build
+    for p in written_paths:
+        assert not os.path.exists(p)
+
+
+def test_is_jetson_false_on_non_aarch64():
+    # Arrange
+    import engines as eng
+
+    with patch("engines.platform") as mock_platform, \
+         patch("engines.tensor_gpu_index", 0), \
+         patch("engines.os.path.isfile", return_value=True):
+        mock_platform.machine.return_value = "x86_64"
+
+        # Assert
+        assert eng._is_jetson() is False
+
+
+def test_is_jetson_false_when_no_gpu():
+    # Arrange
+    import engines as eng
+
+    with patch("engines.platform") as mock_platform, \
+         patch("engines.tensor_gpu_index", -1), \
+         patch("engines.os.path.isfile", return_value=True):
+        mock_platform.machine.return_value = "aarch64"
+
+        # Assert
+        assert eng._is_jetson() is False
+
+
+def test_is_jetson_false_when_no_tegra_release():
+    # Arrange
+    import engines as eng
+
+    with patch("engines.platform") as mock_platform, \
+         patch("engines.tensor_gpu_index", 0), \
+         patch("engines.os.path.isfile", return_value=False):
+        mock_platform.machine.return_value = "aarch64"
+
+        # Assert
+        assert eng._is_jetson() is False