Refactor the exporter into a package-backed module layout.

Split the previous monolithic implementation into focused modules for CLI handling, workflow loading, runtime bootstrap, load ordering, planning, rendering, and file I/O. Keep the public compatibility surface intact by preserving the legacy top-level wrapper while adding  as the documented entrypoint. This reduces cross-cutting coupling inside the exporter and makes the runtime/bootstrap behavior easier to evolve without carrying unrelated concerns in one file.

comfyui_to_python/workflow_loader.py

@@ -0,0 +1,19 @@
+import json
+
+from .io import load_json_input
+
+
+def load_workflow_data(workflow: str, input_file: str):
+    """Load workflow data from inline JSON or an input file."""
+    if input_file:
+        return load_json_input(input_file)
+    return json.loads(workflow)
+
+
+def load_frontend_workflow_data(frontend_workflow: str | dict | None):
+    """Load optional frontend workflow metadata."""
+    if not frontend_workflow:
+        return None
+    if isinstance(frontend_workflow, str):
+        return json.loads(frontend_workflow)
+    return frontend_workflow