refactor: refine separation results layout (#52)

Co-authored-by: Hiroshi Ogawa <4232207+hi-ogawa@users.noreply.github.com>
Co-authored-by: OpenCode <noreply@opencode.ai>

Author: hi-ogawa

packages/app/e2e/separate.spec.ts

@@ -32,7 +32,7 @@ test("separates a clip fully client-side", async ({ page }) => {
   await expect(page.getByTestId("model-progress")).toContainText(
     "htdemucs.onnx",
   );
-  await expect(page.locator("#status")).toContainText("done in", {
+  await expect(page.locator("#status")).toContainText("Done in", {
     timeout: 300_000,
   });
   await expect(page.getByTestId("timing-summary")).toContainText("Inference");