feat(runtime): añade build_graph (StateGraph + routing condicional + interrupt HITL)

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

core/src/agentforge_core/runtime/graph.py

@@ -0,0 +1,72 @@
+"""Compilación del grafo LangGraph para un AgentDefinition concreto."""
+
+from __future__ import annotations
+
+from typing import Any
+
+from langgraph.checkpoint.base import BaseCheckpointSaver
+from langgraph.graph import END, START, StateGraph
+
+from agentforge_core.domain.agent import AgentDefinition
+from agentforge_core.domain.policy import PolicyDefinition
+from agentforge_core.guardrails.base import GuardrailEngine
+from agentforge_core.llm.base import LLMProvider
+from agentforge_core.runtime.nodes import (
+    build_node_approve_gate,
+    build_node_finalize,
+    build_node_llm_reason,
+    build_node_propose_actions,
+    build_node_validate_input,
+    build_node_validate_output,
+)
+from agentforge_core.runtime.state import AgentState
+
+
+def build_graph(
+    *,
+    agent_def: AgentDefinition,
+    policy: PolicyDefinition,
+    provider: LLMProvider,
+    engine: GuardrailEngine,
+    checkpointer: BaseCheckpointSaver[Any],
+) -> Any:
+    """Construye y compila el grafo de ejecución del agente."""
+    g = StateGraph(AgentState)
+
+    g.add_node("validate_input", build_node_validate_input(engine, policy))
+    g.add_node("llm_reason", build_node_llm_reason(provider, agent_def))
+    g.add_node("validate_output", build_node_validate_output(engine, policy))
+    g.add_node("propose_actions", build_node_propose_actions())
+    g.add_node("approve_gate", build_node_approve_gate(agent_def))
+    g.add_node("finalize", build_node_finalize())
+
+    g.add_edge(START, "validate_input")
+
+    def _after_validate_input(state: AgentState) -> str:
+        return END if state.get("status") == "blocked_by_guardrail" else "llm_reason"
+
+    g.add_conditional_edges(
+        "validate_input", _after_validate_input, {END: END, "llm_reason": "llm_reason"}
+    )
+
+    def _after_llm(state: AgentState) -> str:
+        return END if state.get("status") == "failed" else "validate_output"
+
+    g.add_conditional_edges(
+        "llm_reason", _after_llm, {END: END, "validate_output": "validate_output"}
+    )
+
+    def _after_validate_output(state: AgentState) -> str:
+        if state.get("status") in {"blocked_by_guardrail", "failed"}:
+            return END
+        return "propose_actions"
+
+    g.add_conditional_edges(
+        "validate_output", _after_validate_output, {END: END, "propose_actions": "propose_actions"}
+    )
+
+    g.add_edge("propose_actions", "approve_gate")
+    g.add_edge("approve_gate", "finalize")
+    g.add_edge("finalize", END)
+
+    return g.compile(checkpointer=checkpointer)