feat(workflow): load_template returns fresh deep copy per mode

tests/test_workflow.py

@@ -0,0 +1,24 @@
+"""Unit tests for workflow.py — pure functions over JSON dicts."""
+import pytest
+
+import workflow
+
+
+def test_load_template_returns_dict_for_valid_mode():
+    wf = workflow.load_template("t2v")
+    assert isinstance(wf, dict)
+    assert "nodes" in wf
+    assert len(wf["nodes"]) > 0
+
+
+def test_load_template_raises_for_unknown_mode():
+    with pytest.raises(ValueError, match="unknown mode"):
+        workflow.load_template("nonexistent")
+
+
+def test_load_template_returns_independent_copy():
+    """Mutations to one returned dict must not affect later loads."""
+    a = workflow.load_template("t2v")
+    a["nodes"].append({"id": -999})
+    b = workflow.load_template("t2v")
+    assert {-999} & {n.get("id") for n in b["nodes"]} == set()

workflow.py

@@ -0,0 +1,19 @@
+"""Pure functions over LTX 2.3 mode workflow JSON templates."""
+from __future__ import annotations
+
+import copy
+import json
+import pathlib
+from typing import Any
+
+WORKFLOWS_DIR = pathlib.Path(__file__).parent / "workflows"
+
+VALID_MODES: tuple[str, ...] = ("t2v", "a2v", "i2v", "lipsync", "keyframe", "style")
+
+
+def load_template(mode: str) -> dict[str, Any]:
+    """Load a fresh, independent copy of the named mode's workflow template."""
+    if mode not in VALID_MODES:
+        raise ValueError(f"unknown mode {mode!r}; expected one of {VALID_MODES}")
+    path = WORKFLOWS_DIR / f"{mode}.json"
+    return copy.deepcopy(json.loads(path.read_text()))