refactor: add role agent plan ssot

src/role-agent-plan.ts

@@ -0,0 +1,41 @@
+import type { AgentType } from './types.js';
+
+export interface RoleAgentPlan {
+  ownerAgentType: AgentType;
+  reviewerAgentType: AgentType | null;
+  arbiterAgentType: AgentType | null;
+}
+
+export interface ResolveRoleAgentPlanArgs {
+  paired: boolean;
+  groupAgentType?: AgentType;
+  configuredReviewer: AgentType;
+  configuredArbiter?: AgentType | null;
+}
+
+/**
+ * Preserve current runtime agent-resolution behavior in one pure helper.
+ * This intentionally mirrors today's paired inference and does not read room mode yet.
+ */
+export function resolveRoleAgentPlan(
+  args: ResolveRoleAgentPlanArgs,
+): RoleAgentPlan {
+  const ownerAgentType: AgentType = args.groupAgentType || 'claude-code';
+
+  if (!args.paired) {
+    return {
+      ownerAgentType,
+      reviewerAgentType: null,
+      arbiterAgentType: null,
+    };
+  }
+
+  return {
+    ownerAgentType,
+    reviewerAgentType:
+      args.configuredReviewer !== ownerAgentType
+        ? args.configuredReviewer
+        : ownerAgentType,
+    arbiterAgentType: args.configuredArbiter ?? null,
+  };
+}