Delete evaluator.py shim: all imports go directly to bootstrapped sx_ref.py

EvalError moved to types.py. All 27 files updated to import eval_expr,
trampoline, call_lambda, etc. directly from shared.sx.ref.sx_ref instead
of through the evaluator.py indirection layer. 320/320 spec tests pass.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

shared/sx/query_registry.py

@@ -78,7 +78,7 @@ def clear(service: str | None = None) -> None:
 def load_query_file(filepath: str, service_name: str) -> list[QueryDef]:
     """Parse an .sx file and register any defquery definitions."""
     from .parser import parse_all
-    from .evaluator import _eval as _raw_eval, _trampoline
+    from .ref.sx_ref import eval_expr as _raw_eval, trampoline as _trampoline
     _eval = lambda expr, env: _trampoline(_raw_eval(expr, env))
     from .jinja_bridge import get_component_env
 
@@ -103,7 +103,7 @@ def load_query_file(filepath: str, service_name: str) -> list[QueryDef]:
 def load_action_file(filepath: str, service_name: str) -> list[ActionDef]:
     """Parse an .sx file and register any defaction definitions."""
     from .parser import parse_all
-    from .evaluator import _eval as _raw_eval, _trampoline
+    from .ref.sx_ref import eval_expr as _raw_eval, trampoline as _trampoline
     _eval = lambda expr, env: _trampoline(_raw_eval(expr, env))
     from .jinja_bridge import get_component_env