tidy up old code

backend/execution_context.py

@@ -2,7 +2,6 @@ from __future__ import annotations
 
 from contextlib import contextmanager
 from contextvars import ContextVar
-import inspect
 from typing import Any, Callable
 
 Callback = Callable[[str, Any], None]
@@ -13,16 +12,6 @@ _callbacks_var: ContextVar[dict[str, Callback | None]] = ContextVar(
 )
 _node_id_var: ContextVar[str | None] = ContextVar("tono_execution_node_id", default=None)
 
-_LEGACY_CALLBACK_ATTRS = {
-    "preview": "_broadcast_fn",
-    "table": "_broadcast_table_fn",
-    "mesh": "_broadcast_mesh_fn",
-    "overlay": "_broadcast_overlay_fn",
-    "value": "_broadcast_value_fn",
-    "warning": "_broadcast_warning_fn",
-    "file_download": "_broadcast_file_download_fn",
-}
-
 
 @contextmanager
 def execution_callbacks(
@@ -63,42 +52,12 @@ def current_node_id() -> str | None:
     return _node_id_var.get()
 
 
-def _legacy_emit(kind: str, payload: Any) -> bool:
-    callback_attr = _LEGACY_CALLBACK_ATTRS.get(kind)
-    if not callback_attr:
-        return False
-
-    frame = inspect.currentframe()
-    try:
-        frame = frame.f_back
-        while frame is not None:
-            for owner_name in ("self", "cls"):
-                owner = frame.f_locals.get(owner_name)
-                if owner is None:
-                    continue
-
-                candidate = owner if isinstance(owner, type) else owner.__class__
-                callback = getattr(candidate, callback_attr, None)
-                node_id = getattr(candidate, "_current_node_id", None)
-                if callback is not None and node_id:
-                    callback(str(node_id), payload)
-                    return True
-            frame = frame.f_back
-    finally:
-        del frame
-
-    return False
-
-
 def _emit(kind: str, payload: Any) -> None:
     callbacks = _callbacks_var.get()
     callback = callbacks.get(kind)
     node_id = current_node_id()
     if callback is not None and node_id:
         callback(node_id, payload)
-        return
-
-    _legacy_emit(kind, payload)
 
 
 def emit_preview(payload: Any) -> None: