feat(api): implementa router /agents (list, get, versions, get_version, diff)

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

core/src/agentforge_core/api/agents.py

@@ -1,5 +1,50 @@
-"""Router stub de /agents — se implementa en una task posterior."""
+"""Router /agents: listado, detalle, versiones y diff entre versiones."""
 
-from fastapi import APIRouter
+from __future__ import annotations
+
+from typing import Annotated
+
+from fastapi import APIRouter, Depends, HTTPException
+
+from agentforge_core.api.deps import get_registry
+from agentforge_core.domain.agent import AgentDefinition, AgentVersionMeta
+from agentforge_core.registry.repository import FileSystemAgentRegistry
+from agentforge_core.registry.versioning import DiffResult
 
 router = APIRouter()
+
+RegistryDep = Annotated[FileSystemAgentRegistry, Depends(get_registry)]
+
+
+@router.get("", response_model=list[AgentDefinition])
+def list_agents(registry: RegistryDep) -> list[AgentDefinition]:
+    return registry.list_agents()
+
+
+@router.get("/{name}", response_model=AgentDefinition)
+def get_agent(name: str, registry: RegistryDep) -> AgentDefinition:
+    try:
+        return registry.get_agent(name)
+    except FileNotFoundError as exc:
+        raise HTTPException(status_code=404, detail=str(exc)) from exc
+
+
+@router.get("/{name}/versions", response_model=list[AgentVersionMeta])
+def list_versions(name: str, registry: RegistryDep) -> list[AgentVersionMeta]:
+    try:
+        return registry.list_versions(name)
+    except FileNotFoundError as exc:
+        raise HTTPException(status_code=404, detail=str(exc)) from exc
+
+
+@router.get("/{name}/versions/{version}", response_model=AgentDefinition)
+def get_version(name: str, version: str, registry: RegistryDep) -> AgentDefinition:
+    try:
+        return registry.get_version(name, version)
+    except FileNotFoundError as exc:
+        raise HTTPException(status_code=404, detail=str(exc)) from exc
+
+
+@router.get("/{name}/versions/{v_from}/diff/{v_to}", response_model=DiffResult)
+def diff_versions(name: str, v_from: str, v_to: str, registry: RegistryDep) -> DiffResult:
+    return registry.diff_versions(name, v_from, v_to)