feat(engine): enable CanvasDrawElement in renderer Chrome args

Cherry-picked from feat/html-in-canvas-launch (PR #611):

- Enable --enable-features=CanvasDrawElement in Chrome browser args
  so HTML-in-canvas compositions render correctly
- Add native drawElementImage() capture path for shader transitions
  with existing fallback preserved
- Reuse renderer Chrome args in hyperframes validate for consistent
  WebGL/CanvasDrawElement environment
- Add capture.test.ts for the new shader transition capture path

packages/engine/src/services/browserManager.test.ts

@@ -7,6 +7,7 @@ describe("buildChromeArgs browser GPU mode", () => {
 
   it("uses SwiftShader software GL by default for reproducible local renders", () => {
     const args = buildChromeArgs(base);
+    expect(args).toContain("--enable-features=CanvasDrawElement");
     expect(args).toContain("--use-gl=angle");
     expect(args).toContain("--use-angle=swiftshader");
     expect(args).not.toContain("--enable-gpu-rasterization");