refactor: replace orchestrator with LangGraph deep-agent supervisors

- Add app/core/deep_agent.py with Home and Floating supervisor graphs
  using LangGraph create_react_agent (hierarchical pattern)
- Strip ChatAgent classes from all 4 agent files, keep @tool functions
- Rewrite output_formatter.py for event-based (token/tool_end/mutations) stream
- Update device_ws.py to use run_home_stream/run_floating_stream
- Rewrite chat.py REST route to use run_home
- Add update_core_memory tool to both supervisors
- Add langgraph>=0.3.0 to requirements.txt
- Remove orchestrator.py, execution_plan.py, agent_registry.py, plans.py
- Remove PlanAction, PlanStep, ExecutionPlan, execution_mode from schemas
- Update all affected tests to match new API
- Remove 6 deprecated test files for deleted modules
- Clean up stale docstrings referencing removed orchestrator

app/core/ws_context.py

@@ -7,18 +7,21 @@ The callback sends a `tool_call` WS frame and awaits the `tool_result`.
 
 from __future__ import annotations
 
+import logging
 from contextvars import ContextVar
 from typing import Any, Callable, Coroutine
 from uuid import uuid4
 
+logger = logging.getLogger(__name__)
+
 # Holds the execute callback for the current WS session.
-# Set by the chat WS handler before the orchestrator runs; cleared after.
+# Set by the chat WS handler before the deep agent runs; cleared after.
 _client_executor: ContextVar[Callable[[dict], Coroutine[Any, Any, dict]]] = ContextVar(
     "_client_executor"
 )
 
 # Optional collector that captures raw execute_on_client results.
-# Set by _tool_loop / _tool_loop_stream to populate ChatAgent.tool_results.
+# Set by the deep agent tool loop to capture CRUD mutations.
 _tool_result_collector: ContextVar[list[dict] | None] = ContextVar(
     "_tool_result_collector", default=None
 )
@@ -81,7 +84,12 @@ async def execute_on_client(
     if limit is not None:
         payload["limit"] = limit
 
+    logger.info("execute_on_client: sending payload action=%s table=%s id=%s", action, table, payload["id"])
     result = await callback(payload)
+    if result is None:
+        logger.error("execute_on_client: callback returned None for action=%s table=%s id=%s", action, table, payload["id"])
+    else:
+        logger.info("execute_on_client: got result type=%s keys=%s", type(result).__name__, list(result.keys()) if isinstance(result, dict) else "N/A")
     collector = _tool_result_collector.get(None)
     if collector is not None:
         collector.append({