feat(agent): budget reminders, usage while waiting, budget-exceeded status and dedupe

- tool results carry a budget reminder near limits; text before the last tool
  call is dropped as report when cut by budget/abort
- usage persisted when a run suspends, so waiting sessions show spent tokens
- task page shows budget_exceeded via business.outcome instead of completed
- budget-exceeded decisions merge by root cause (decision / schedule / goal
  template); new summaries added to investigate allowlist

Co-Authored-By: Claude Opus 5.5 <[email protected]>

packages/agent/test/runtime.test.ts

@@ -270,6 +270,34 @@ describe("PiAgentRuntime + FakeModelProvider", () => {
     expect(fx.audits.filter((a) => a.capabilityId === "inventory.query")).toHaveLength(2);
   });
 
+  it("预算将尽:工具结果追加【预算提醒】;被预算截断时中间过程文字不作为汇报", async () => {
+    const fx = makeFixture();
+    const loop: FakeScript = {
+      match: "Dune",
+      steps: Array.from({ length: 10 }, () => ({
+        text: "Let me check the inventory again.",
+        toolCalls: [{ capability: "inventory.query", input: { title: "Dune" } }],
+      })),
+      finalText: "不该到这里",
+    };
+    const { run, fake } = await start(fx, [loop], { settings: { maxToolCalls: 4 } });
+    const out = await run.prompt();
+    expect(out).toMatchObject({ status: "failed", reason: "budget", budget: "tool_calls", finalText: "" });
+    expect(fake.lastRequest?.transcript).toContain("【预算提醒】工具调用只剩 2 次");
+  });
+
+  it("预算:收尾文字在最后一次工具调用之后 → 被截断时仍保留为汇报", async () => {
+    const fx = makeFixture();
+    const script: FakeScript = {
+      match: "Dune",
+      steps: [{ toolCalls: [{ capability: "inventory.query", input: { title: "Dune" } }] }],
+      finalText: "小结:库里没有 Dune。",
+    };
+    const { run } = await start(fx, [script], { settings: { maxToolCalls: 5 } });
+    const out = await run.prompt();
+    expect(out).toMatchObject({ status: "completed", finalText: "小结:库里没有 Dune。" });
+  });
+
   it("预算:运行时长超限 → run_failed(budget/duration)", async () => {
     const fx = makeFixture({ slowMs: 5_000 });
     fx.grants.set("user:1", new Set(["download.submit"]));