Display executionPlan in UI; add tests for Trader executionPlan parsing and TradingGraph execution step

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

app/agents/__tests__/tradingGraph.execution.test.ts

@@ -0,0 +1,30 @@
+import { describe, it, expect, vi } from "vitest";
+import { TradingGraph } from "../tradingGraph";
+
+describe("TradingGraph execution step", () => {
+  it("returns executionPlan when model provides it", async () => {
+    const mockClient = {
+      createChatCompletion: vi.fn().mockResolvedValue({
+        choices: [{ message: { content: JSON.stringify({
+          action: "sell",
+          confidence: 0.85,
+          reasoning: "Test sell",
+          executionPlan: { amount: 100, riskManagement: { maxLossPercent: 2 }, takeProfit: 200 }
+        }) } }]
+      }),
+    };
+
+    const mockInput = {
+      financialData: "...",
+      technicalData: { prices: [1,2,3], sma: 1, ema: 1, rsi: 50, macd: 0 },
+      sentimentData: { headlines: ["h"], source: "news" },
+    };
+
+    const graph = new TradingGraph(mockClient as any);
+    const decision = await graph.propagate("AAPL", mockInput as any);
+
+    expect(decision.action).toBe("sell");
+    expect(decision.executionPlan).toBeDefined();
+    expect(decision.executionPlan?.amount).toBe(100);
+  });
+});