fix: core service launcher missing CADIntegration bin folder in path (#1958)

Co-authored-by: pyansys-ci-bot <92810346+pyansys-ci-bot@users.noreply.github.com>
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

Author: 3 people

doc/changelog.d/1958.fixed.md

@@ -0,0 +1 @@
+core service launcher missing CADIntegration bin folder in path

src/ansys/geometry/core/connection/product_instance.py

@@ -384,6 +384,7 @@ def prepare_and_start_backend(
             root_service_folder = Path(root_service_folder)
         native_folder = root_service_folder / "Native"
         cad_integration_folder = root_service_folder / "CADIntegration"
+        cad_integration_folder_bin = cad_integration_folder / "bin"
         schema_folder = root_service_folder / "Schema"
 
         # Adapt the native folder to the OS
@@ -421,15 +422,20 @@ def prepare_and_start_backend(
         else:
             env_copy["LICENSE_SERVER"] = os.getenv("ANSYSLMD_LICENSE_FILE", "1055@localhost")
 
-        if os.name == "nt":
-            # Modify the PATH variable to include the path to the Ansys Geometry Core Service
-            env_copy["PATH"] = (
-                f"{env_copy['PATH']}"
-                + f";{root_service_folder.as_posix()}"
-                + f";{native_folder.as_posix()}"
-                + f";{cad_integration_folder.as_posix()}"
-            )
+        # Adapt the path environment variable to the OS and
+        # modify the PATH/LD_LIBRARY_PATH variable to include the path
+        # to the Ansys Geometry Core Service
+        path_env_var = "PATH" if os.name == "nt" else "LD_LIBRARY_PATH"
+        env_copy[path_env_var] = os.pathsep.join(
+            [
+                root_service_folder.as_posix(),
+                native_folder.as_posix(),
+                cad_integration_folder_bin.as_posix(),
+                env_copy.get(path_env_var, ""),
+            ]
+        )
 
+        if os.name == "nt":
             # For Windows, we need to use the exe file to launch the Core Geometry Service
             args.append(
                 Path(
@@ -456,14 +462,6 @@ def prepare_and_start_backend(
                     "Please install a compatible version."
                 )
 
-            # Modify the LD_LIBRARY_PATH variable to include the Ansys Geometry Core Service
-            env_copy["LD_LIBRARY_PATH"] = (
-                env_copy.get("LD_LIBRARY_PATH", "")
-                + f":{root_service_folder.as_posix()}"
-                + f":{native_folder.as_posix()}"
-                + f":{cad_integration_folder.as_posix()}"
-            )
-
             # For Linux, we need to use the dotnet command to launch the Core Geometry Service
             args.append("dotnet")
             args.append(