feat: testing scaled screenshots to normalized coordinate space

test/model.test.ts

@@ -1,7 +1,7 @@
 import { test } from "node:test";
 import assert from "node:assert/strict";
 import { complete } from "../src/model.js";
-import { desktopArguments, shellArguments, toolsForCoordinates } from "../src/tools.js";
+import { desktopArguments, scaleImage, shellArguments, toolsForCoordinates } from "../src/tools.js";
 
 const config: import("../src/config.js").Config = { coordinateSpace: "pixels", llamaCppOrigin: "http://example.test", modelId: "test", databasePath: ":memory:" };
 
@@ -37,3 +37,9 @@ test("tool inputs reject invalid commands, bounds, and action names", () => {
     assert.throws(() => desktopArguments.parse({ actions: [{ type: "click_target", target: "1" }] }));
     assert.equal(desktopArguments.parse({ actions: [{ type: "click_target", target: "1", observationId: "frame" }] }).actions[0]?.type, "click_target");
 });
+
+test("scaleImage resizes PNG to requested dimensions", async () => {
+    const buffer = await scaleImage("artifacts/first.png", 1000, 1000);
+    assert.ok(Buffer.isBuffer(buffer));
+    assert.ok(buffer.length > 0);
+});