test(sidecar): add fixture asus-ga403wr-ryzen-ai9-hx370-rtx5070ti-dgpu-active

Sibling of the existing igpu-only tree for the same machine
(ROG Zephyrus G14 GA403WR). This capture has both the AMD Radeon 890M
(iGPU) and NVIDIA RTX 5070 Ti Laptop GPU present in the sensor tree —
the dGPU was absent (Optimus/idle) in the original fixture.

Also updates the original meta.json to document gpu_state: igpu-only
and point to the new sibling.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>