fix(pcie): stop misclassifying same-vendor non-GPU devices as GPUs

matchesGPUVendor (sat_overlay.go) matched any PCIe DeviceClass containing
the substring "Controller" instead of the actual GPU classes, so a
same-vendor non-GPU device (e.g. an NVIDIA-branded NIC/storage controller)
with a degraded PCIe link surfaced as a pcie:gpu:<vendor> alarm on the
Hardware Summary/webui.

isGPUDevice (app_format.go) had the same bug via a different path: an
"any NVIDIA-vendor device is a GPU" fallback that could inflate the
"GPU: N x <model>" audit summary line with non-GPU companion devices
(NVSwitch/NVLink bridges, etc).

Both now defer to collector.IsGPUClass (exported from the previously
unexported isGPUClass), the canonical exact-match classifier already used
by amdgpu.go — removing the duplicated/incorrect class checks instead of
reimplementing them. Also dedup two more locally-duplicated classifiers
within webui (which doesn't import collector by convention): NIC-class
matching (pages.go/page_topo.go) and GPU-class matching in
page_validate.go now share one copy per package instead of being
reimplemented per file.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

audit/internal/app/app_format_test.go

@@ -0,0 +1,32 @@
+package app
+
+import (
+	"testing"
+
+	"bee/audit/internal/schema"
+)
+
+// TestFormatGPULineIgnoresNonGPUSameVendorDevice guards the bug where
+// isGPUDevice treated any NVIDIA-vendor PCIe device as a GPU regardless of
+// class (a fallback for "NVIDIA devices sometimes expose class values
+// outside the standard GPU set"). That fallback misclassified same-vendor
+// companion devices — e.g. NVSwitch/NVLink bridges, or an NVIDIA-branded NIC
+// — as compute GPUs, inflating the "GPU: N x <model>" audit summary line.
+func TestFormatGPULineIgnoresNonGPUSameVendorDevice(t *testing.T) {
+	vendor := 0x10de // collector.NvidiaVendorID
+	bridgeClass := "Bridge"
+	bridgeModel := "NVSwitch"
+	gpuClass := "VideoController"
+	gpuModel := "H100"
+
+	devices := []schema.HardwarePCIeDevice{
+		{DeviceClass: &bridgeClass, VendorID: &vendor, Model: &bridgeModel},
+		{DeviceClass: &gpuClass, VendorID: &vendor, Model: &gpuModel},
+	}
+
+	got := formatGPULine(devices)
+	want := "GPU: 1 x H100"
+	if got != want {
+		t.Fatalf("formatGPULine() = %q, want %q", got, want)
+	}
+}