Parent: #1296

Problem

get_gpu_name_from_lspci_by_vendor_id("1002") in lspci.rs returns the first VGA device matching vendor ID 0x1002. When a system has both an AMD iGPU (e.g., Renoir integrated Radeon Graphics) and a discrete AMD GPU (e.g., Radeon RX 7900), both share vendor 0x1002, so both GPUs are assigned the same name.

Since GPU name is the key in gpu_usage_histories / gpu_temperature_histories HashMap and the gpu_name column in GPU_DATA_ARCHIVE, this causes:

• One GPU's metrics overwriting the other in real-time history
• Both GPUs stored under the same name in the archive DB
• Only one tab appearing in Insights even though two GPUs exist

Additionally, get_gpu_usage() in platform/linux/gpu.rs returns on the first AMD card found, completely ignoring the second GPU.

Affected Files

• src-tauri/src/infrastructure/providers/linux/lspci.rs — get_gpu_name_from_lspci_by_vendor_id() returns first match only
• src-tauri/src/infrastructure/providers/linux/drm_sys.rs — needs BDF extraction from sysfs
• src-tauri/src/services/monitoring_service.rs — collect_linux_gpu_metrics() uses vendor-ID-based name lookup
• src-tauri/src/platform/linux/gpu.rs — get_amd_graphic_info() uses same broken lookup; get_gpu_usage() returns first AMD card only

Proposed Solution

1. Add BDF extraction in drm_sys.rs: read the PCI address from the sysfs symlink at /sys/class/drm/card{N}/device (e.g., ../../0000:03:00.0) to get the bus:device.function tuple

2. Add BDF-based lspci lookup in lspci.rs: match the specific PCI slot (e.g., 03:00.0) from lspci -nn output instead of matching by vendor ID alone

3. Update collect_linux_gpu_metrics() to use BDF-based name resolution for each card individually

4. Update get_amd_graphic_info() to accept and use the card's BDF for name resolution

5. Fix get_gpu_usage() to not early-return on first AMD card (or deprecate in favor of sample_gpu() which already handles multiple GPUs)

Fallback

If BDF resolution fails (e.g., unusual kernel configuration), fall back to "AMD GPU (card{N})" format using the card ID, which at least ensures uniqueness.