fix: complete ebay integer validation test coverage

packages/api-server/test/routes.test.ts

@@ -633,6 +633,78 @@ describe("API routes", () => {
     expect(body.message).toBe("Invalid maxItems parameter");
   });
 
+  test("ebayRoute returns 400 for empty minPrice", async () => {
+    const { ebayRoute } = await import("../src/routes/ebay");
+
+    const response = await ebayRoute(
+      new Request("http://localhost/api/ebay?q=laptop&minPrice="),
+    );
+
+    expect(response.status).toBe(400);
+    const body = await response.json();
+    expect(body.message).toBe("Invalid minPrice parameter");
+  });
+
+  test("ebayRoute returns 400 for whitespace minPrice", async () => {
+    const { ebayRoute } = await import("../src/routes/ebay");
+
+    const response = await ebayRoute(
+      new Request("http://localhost/api/ebay?q=laptop&minPrice=%20%20"),
+    );
+
+    expect(response.status).toBe(400);
+    const body = await response.json();
+    expect(body.message).toBe("Invalid minPrice parameter");
+  });
+
+  test("ebayRoute returns 400 for hex minPrice", async () => {
+    const { ebayRoute } = await import("../src/routes/ebay");
+
+    const response = await ebayRoute(
+      new Request("http://localhost/api/ebay?q=laptop&minPrice=0x10"),
+    );
+
+    expect(response.status).toBe(400);
+    const body = await response.json();
+    expect(body.message).toBe("Invalid minPrice parameter");
+  });
+
+  test("ebayRoute returns 400 for empty maxPrice", async () => {
+    const { ebayRoute } = await import("../src/routes/ebay");
+
+    const response = await ebayRoute(
+      new Request("http://localhost/api/ebay?q=laptop&maxPrice="),
+    );
+
+    expect(response.status).toBe(400);
+    const body = await response.json();
+    expect(body.message).toBe("Invalid maxPrice parameter");
+  });
+
+  test("ebayRoute returns 400 for whitespace maxPrice", async () => {
+    const { ebayRoute } = await import("../src/routes/ebay");
+
+    const response = await ebayRoute(
+      new Request("http://localhost/api/ebay?q=laptop&maxPrice=%20%20"),
+    );
+
+    expect(response.status).toBe(400);
+    const body = await response.json();
+    expect(body.message).toBe("Invalid maxPrice parameter");
+  });
+
+  test("ebayRoute returns 400 for hex maxPrice", async () => {
+    const { ebayRoute } = await import("../src/routes/ebay");
+
+    const response = await ebayRoute(
+      new Request("http://localhost/api/ebay?q=laptop&maxPrice=0x10"),
+    );
+
+    expect(response.status).toBe(400);
+    const body = await response.json();
+    expect(body.message).toBe("Invalid maxPrice parameter");
+  });
+
   test("ebayRoute returns 400 for non-integer minPrice", async () => {
     const { ebayRoute } = await import("../src/routes/ebay");