verbose live UI + tool-level SSE events + Groq default + regression tests

api/runtime/state.py

@@ -0,0 +1,20 @@
+"""Shared state passed between runtime nodes.
+
+This is the one type langgraph sees. Domain code in api/plan, api/analyses,
+api/tools never imports it — they take/return their own dataclasses.
+"""
+
+from __future__ import annotations
+
+from typing import Annotated, Any, TypedDict
+from operator import add
+
+
+class RunState(TypedDict, total=False):
+    run_id: str
+    question: str
+    plan_rationale: str
+    plan_steps: list[dict[str, Any]]      # serialised PlanStep
+    findings: Annotated[list[dict[str, Any]], add]   # serialised Finding; concatenated by langgraph
+    answer: str
+    error: str