更新环境配置示例，添加 GRVT 相关的 API 凭证和选项，增强文档以支持新的交易所适配器，确保用户能够正确配置和使用 GRVT 交易功能。

tests/exchange-factory.test.ts

@@ -0,0 +1,42 @@
+import { describe, expect, it, beforeEach, afterEach } from "vitest";
+import { createExchangeAdapter, resolveExchangeId } from "../src/exchanges/create-adapter";
+import { AsterExchangeAdapter } from "../src/exchanges/aster-adapter";
+import { GrvtExchangeAdapter } from "../src/exchanges/grvt/adapter";
+
+const ORIGINAL_ENV = { ...process.env };
+
+beforeEach(() => {
+  process.env = { ...ORIGINAL_ENV };
+});
+
+afterEach(() => {
+  process.env = { ...ORIGINAL_ENV };
+});
+
+describe("exchange factory", () => {
+  it("defaults to aster when no env is provided", () => {
+    delete process.env.EXCHANGE;
+    const adapter = createExchangeAdapter({ symbol: "BTCUSDT" });
+    expect(adapter).toBeInstanceOf(AsterExchangeAdapter);
+    expect(adapter.id).toBe("aster");
+  });
+
+  it("resolves exchange id case-insensitively", () => {
+    expect(resolveExchangeId("Grvt")).toBe("grvt");
+    expect(resolveExchangeId("ASTER")).toBe("aster");
+  });
+
+  it("creates grvt adapter when EXCHANGE=grvt", () => {
+    process.env.EXCHANGE = "grvt";
+    process.env.GRVT_API_KEY = "api-key";
+    process.env.GRVT_API_SECRET = "0x" + "1".repeat(64);
+    process.env.GRVT_SUB_ACCOUNT_ID = "sub";
+    process.env.GRVT_INSTRUMENT = "BTC_USDT_Perp";
+    process.env.GRVT_SYMBOL = "BTCUSDT";
+    delete process.env.GRVT_SIGNER_PATH;
+
+    const adapter = createExchangeAdapter({ symbol: "BTCUSDT" });
+    expect(adapter).toBeInstanceOf(GrvtExchangeAdapter);
+    expect(adapter.id).toBe("grvt");
+  });
+});