refactor: move `run_loop into strix/orchestration/`

Top-level ``strix/run_loop.py`` was an orphan — it owns the multi-agent
continuation loop, which is exactly the orchestration layer's job.
Moves it into ``strix/orchestration/run_loop.py`` next to the bus,
hooks, and filter — they all glue ``Runner.run`` to bus state.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

strix/entry.py

@@ -26,12 +26,12 @@ from strix.agents.factory import build_strix_agent, make_child_factory
 from strix.config import load_settings
 from strix.orchestration.bus import AgentMessageBus
 from strix.orchestration.hooks import StrixOrchestrationHooks
+from strix.orchestration.run_loop import run_with_continuation
 from strix.run_config_factory import (
     STRIX_DEFAULT_MAX_TURNS,
     make_agent_context,
     make_run_config,
 )
-from strix.run_loop import run_with_continuation
 from strix.runtime import session_manager
 
 

strix/tools/agents_graph/tools.py

@@ -25,8 +25,8 @@ from agents import RunContextWrapper, function_tool
 from agents.items import TResponseInputItem
 
 from strix.orchestration.hooks import StrixOrchestrationHooks
+from strix.orchestration.run_loop import run_with_continuation
 from strix.run_config_factory import make_agent_context, make_run_config
-from strix.run_loop import run_with_continuation
 
 
 if TYPE_CHECKING: