refactor(chat): drop alternate streaming entry path; use graph_stream

surfsense_backend/app/tasks/chat/streaming/relay/__init__.py

@@ -1,7 +1,23 @@
-"""Relay state: thinking steps, tool bookkeeping, and stream helpers."""
+"""Relay: thinking steps, tool bookkeeping, and ``EventRelay``.
+
+Package imports are lazy so ``relay.thinking_step_sse`` (and siblings) can load
+without pulling in ``event_relay`` (which imports handler modules that may
+import those siblings).
+"""
 
 from __future__ import annotations
 
-from app.tasks.chat.streaming.relay.event_relay import EventRelay, EventRelayConfig
-
 __all__ = ["EventRelay", "EventRelayConfig"]
+
+
+def __getattr__(name: str):
+    if name == "EventRelay":
+        from app.tasks.chat.streaming.relay.event_relay import EventRelay
+
+        return EventRelay
+    if name == "EventRelayConfig":
+        from app.tasks.chat.streaming.relay.event_relay import EventRelayConfig
+
+        return EventRelayConfig
+    msg = f"module {__name__!r} has no attribute {name!r}"
+    raise AttributeError(msg)

surfsense_backend/app/tasks/chat/streaming/relay/event_relay.py

@@ -7,6 +7,7 @@ from dataclasses import dataclass, field
 from typing import Any
 
 from app.services.streaming.emitter import EmitterRegistry
+from app.tasks.chat.streaming.graph_stream.result import StreamingResult
 from app.tasks.chat.streaming.handlers.chain_end import iter_chain_end_frames
 from app.tasks.chat.streaming.handlers.chat_model_stream import (
     iter_chat_model_stream_frames,
@@ -16,7 +17,6 @@ from app.tasks.chat.streaming.handlers.custom_event_dispatch import (
 )
 from app.tasks.chat.streaming.handlers.tool_end import iter_tool_end_frames
 from app.tasks.chat.streaming.handlers.tool_start import iter_tool_start_frames
-from app.tasks.chat.streaming.orchestration.output import StreamingResult
 from app.tasks.chat.streaming.relay.state import AgentEventRelayState
 from app.tasks.chat.streaming.relay.thinking_step_completion import (
     complete_active_thinking_step,