refactor(core): extract shared dedup helpers

src/agents/trace-base.ts

@@ -0,0 +1,21 @@
+export type AgentTraceBase = {
+  runId?: string;
+  sessionId?: string;
+  sessionKey?: string;
+  provider?: string;
+  modelId?: string;
+  modelApi?: string | null;
+  workspaceDir?: string;
+};
+
+export function buildAgentTraceBase(params: AgentTraceBase): AgentTraceBase {
+  return {
+    runId: params.runId,
+    sessionId: params.sessionId,
+    sessionKey: params.sessionKey,
+    provider: params.provider,
+    modelId: params.modelId,
+    modelApi: params.modelApi,
+    workspaceDir: params.workspaceDir,
+  };
+}