refactor(core): rename agent_runner/session_buffer/registry to scout_*

app/core/deep_agent.py

@@ -18,7 +18,7 @@ from app.agents.project_agent import PROJECT_TOOLS
 from app.agents.relations_agent import make_query_relations_tool
 from app.agents.task_agent import TASK_TOOLS
 from app.agents.timeline_agent import TIMELINE_TOOLS
-from app.core.agent_session_buffer import session_buffer
+from app.core.scout_session_buffer import session_buffer
 from app.core.langfuse_client import compile_prompt, extract_usage, get_langfuse, get_prompt_or_fallback, langfuse_context
 from app.core.llm import get_agent_llm, model_for_agent
 from app.core.memory_middleware import MemoryMiddleware