consolidate: HQ LangGraph StateGraph orchestration

hq/langgraph_graph.py

@@ -0,0 +1,63 @@
+"""
+Agent Q3 [HQ] — LangGraph StateGraph
+Multi-agent routing: classify → reasoner | coder → tandem (optional) → output
+"""
+from langgraph.graph import StateGraph, END
+from typing import TypedDict, Literal
+import asyncio
+
+class AgentState(TypedDict):
+    messages: list
+    target: str
+    plan: str
+    output: str
+    route: str
+
+def classify_node(state: AgentState) -> AgentState:
+    content = " ".join(m.get("content","") for m in state["messages"]).lower()
+    code_kw = ["fix","debug","implement","write","function","class","solidity","contract"]
+    state["route"] = "coder" if any(k in content for k in code_kw) else "reasoner"
+    return state
+
+async def reasoner_node(state: AgentState) -> AgentState:
+    from compute_router import ComputeRouter
+    router = ComputeRouter()
+    result = await router.route(state["messages"], target="reasoner")
+    state["output"] = result["choices"][0]["message"]["content"]
+    return state
+
+async def coder_node(state: AgentState) -> AgentState:
+    from compute_router import ComputeRouter
+    router = ComputeRouter()
+    result = await router.route(state["messages"], target="coder")
+    state["output"] = result["choices"][0]["message"]["content"]
+    return state
+
+async def tandem_node(state: AgentState) -> AgentState:
+    from tandem_core import TandemCore
+    result = await TandemCore().run(state["messages"])
+    state["plan"]   = result["plan"]
+    state["output"] = result["implementation"]
+    return state
+
+def route_decision(state: AgentState) -> Literal["reasoner", "coder", "tandem"]:
+    return state.get("route", "reasoner")
+
+def build_graph() -> StateGraph:
+    g = StateGraph(AgentState)
+    g.add_node("classify", classify_node)
+    g.add_node("reasoner", reasoner_node)
+    g.add_node("coder",    coder_node)
+    g.add_node("tandem",   tandem_node)
+    g.set_entry_point("classify")
+    g.add_conditional_edges("classify", route_decision, {
+        "reasoner": "reasoner",
+        "coder":    "coder",
+        "tandem":   "tandem",
+    })
+    g.add_edge("reasoner", END)
+    g.add_edge("coder",    END)
+    g.add_edge("tandem",   END)
+    return g.compile()
+
+graph = build_graph()