优化流程

backend/engine/cdsl_engine/__init__.py

@@ -8,7 +8,24 @@ from __future__ import annotations
 
 from .llm_compiler import compile_cdsl
 from .llm_engine import run_engine_plan
-from .rebuild import compare_with_gold, compile_cdsl_to_pack, run_cdsl_only, run_engine, run_rebuild
+try:
+    from .rebuild import compare_with_gold, compile_cdsl_to_pack, run_cdsl_only, run_engine, run_rebuild
+except ModuleNotFoundError as exc:
+    # The legacy rebuild façade optionally depends on cdsl_importer, which is
+    # not present in the standalone runtime distribution.  Keep importing the
+    # executable session runtime possible; callers of the legacy façade get a
+    # precise import error when they invoke it.
+    if exc.name != "cdsl_importer":
+        raise
+
+    def _legacy_rebuild_unavailable(*_args, _missing=exc, **_kwargs):
+        raise RuntimeError("legacy rebuild facade requires the optional cdsl_importer package") from _missing
+
+    compare_with_gold = _legacy_rebuild_unavailable
+    compile_cdsl_to_pack = _legacy_rebuild_unavailable
+    run_cdsl_only = _legacy_rebuild_unavailable
+    run_engine = _legacy_rebuild_unavailable
+    run_rebuild = _legacy_rebuild_unavailable
 from .semantic_validation import validate_semantic_cdsl
 from .sketch_solver import CORE_SHAPE_GENERATORS, resolve_all_sketches, resolve_required_sketches
 from .runtime import ALL_ATOMIC_IDS, EXECUTORS, RuntimeExecutionError, analyze_cdsl, rebuild_cdsl