feat(langfuse): propagate user_id and session_id to all traces

- Add hash_user_id() to SHA-256 hash user IDs before sending to Langfuse
- Add langfuse_context() helper wrapping propagate_attributes()
- deep_agent: extract session_id from _debug context, wrap all agent
  runs and classifier with langfuse_context(user_id, session_id)
- agent_runner: add session_id param, pass run_id as session for batch
- agent_setup: wrap journey LLM calls with langfuse_context
- Remove redundant metadata dicts (now handled by propagate_attributes)

app/core/agent_runner.py

@@ -44,7 +44,7 @@ from app.agents.project_agent import PROJECT_TOOLS
 from app.agents.task_agent import TASK_TOOLS
 from app.agents.timeline_agent import TIMELINE_TOOLS
 from app.core.device_manager import DeviceConnectionManager
-from app.core.langfuse_client import compile_prompt, extract_usage, get_langfuse, get_prompt_or_fallback
+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.preprocessors import detect_content_type, preprocess
 from app.core.ws_context import clear_client_executor, execute_on_client, set_client_executor
@@ -227,6 +227,7 @@ async def _run_agent_with_tools(
     tools: list[Any],
     max_steps: int,
     user_id: str = "",
+    session_id: str = "",
     langfuse_prompt: Any = None,
     agent_name: str = "batch-agent",
     _tool_calls_out: list[str] | None = None,
@@ -246,6 +247,9 @@ async def _run_agent_with_tools(
 
     tool_map = {tool_def.name: tool_def for tool_def in tools}
 
+    _lf_ctx = langfuse_context(user_id=user_id or None, session_id=session_id or None)
+    _lf_ctx.__enter__()
+
     _span_ctx = (
         lf.start_as_current_observation(
             as_type="span",
@@ -272,7 +276,7 @@ async def _run_agent_with_tools(
             _gen = _gen_ctx.__enter__() if _gen_ctx else None
             response: AIMessage = await llm_with_tools.ainvoke(messages)
             if _gen_ctx:
-                _gen.update(output=_as_text(response.content), usage=extract_usage(response))
+                _gen.update(output=_as_text(response.content), usage_details=extract_usage(response))
                 _gen_ctx.__exit__(None, None, None)
 
             messages.append(response)
@@ -317,6 +321,7 @@ async def _run_agent_with_tools(
     finally:
         if _span_ctx:
             _span_ctx.__exit__(None, None, None)
+        _lf_ctx.__exit__(None, None, None)
         if lf:
             lf.flush()
 
@@ -385,7 +390,8 @@ async def _scan_directories(
     for file_path in all_files:
         try:
             meta = await execute_on_client(action="get_file_metadata", data={"path": file_path})
-            modified_at = meta.get("modifiedAt")
+            # FE sends snake_case keys on the wire (toSnakeCase transform)
+            modified_at = meta.get("modified_at") or meta.get("modifiedAt")
             if modified_at is None:
                 filtered.append(file_path)
                 continue
@@ -606,7 +612,6 @@ async def run_local_agent(
 
     try:
         # ── Code: scan directories ───────────────────────────────────
-        logger.info("agent_runner: run=%s scanning directories user=%s", run_id, user_id)
         file_paths = await _scan_directories(
             paths=config.directory_paths,
             extensions=config.file_extensions or [],
@@ -685,6 +690,7 @@ async def run_local_agent(
                     tools=processing_tools,
                     max_steps=_MAX_PROCESSING_STEPS,
                     user_id=user_id,
+                    session_id=run_id,
                     langfuse_prompt=prompt_obj,
                     agent_name="unified-processor",
                     _tool_calls_out=file_tool_calls,
@@ -916,6 +922,7 @@ async def run_cloud_agent(
                     tools=processing_tools,
                     max_steps=_MAX_PROCESSING_STEPS,
                     user_id=user_id,
+                    session_id=run_id,
                     langfuse_prompt=cloud_prompt_obj,
                     agent_name="cloud-processor",
                 )