Initial commit: full Phases 1-6 implementation

Post-repair hardware validation pipeline for Proxmox cluster hosts.
Go orchestrator + in-image agent + mkosi live image + bundled dnsmasq
PXE + SQLite + HTMX/SSE UI + notify registry + janitor + full docs.

agent/tests/gpu.go

@@ -0,0 +1,86 @@
+package tests
+
+import (
+	"context"
+	"os/exec"
+	"strings"
+)
+
+// GPU enumerates VGA / 3D PCI devices. No devices → skip cleanly (a
+// CPU-only server passes this stage by virtue of having nothing to
+// stress). Devices present → try nvidia-smi for NVIDIA cards, else
+// accept PCI presence.
+func GPU(ctx context.Context, d Deps) Outcome {
+	devices := listGPUPCI(ctx)
+	if len(devices) == 0 {
+		d.Info("GPU: no VGA/3D PCI devices found — skipping stage")
+		return Outcome{
+			Passed:  true,
+			Summary: "skipped (no GPU present)",
+			Extras:  map[string]any{"skipped": true, "reason": "no_gpu_present"},
+		}
+	}
+	d.Info("GPU: found " + joinDevices(devices))
+
+	nvidia := nvidiaSmiList(ctx)
+	extras := map[string]any{
+		"pci_devices": devices,
+		"skipped":     false,
+	}
+	if len(nvidia) > 0 {
+		extras["nvidia"] = nvidia
+		d.Info("GPU: nvidia-smi reports: " + strings.Join(nvidia, ", "))
+	}
+	return Outcome{
+		Passed:  true,
+		Summary: formatCount(len(devices), "GPU present"),
+		Extras:  extras,
+	}
+}
+
+// listGPUPCI shells out to lspci. Returns human-readable strings, one
+// per VGA/3D device. If lspci isn't available we return nil and the
+// caller treats it as "no GPU" which auto-skips.
+func listGPUPCI(ctx context.Context) []string {
+	cmd := exec.CommandContext(ctx, "lspci", "-mm")
+	out, err := cmd.Output()
+	if err != nil {
+		return nil
+	}
+	var devs []string
+	for _, line := range strings.Split(string(out), "\n") {
+		l := strings.ToLower(line)
+		if strings.Contains(l, "vga compatible controller") || strings.Contains(l, "3d controller") {
+			devs = append(devs, strings.TrimSpace(line))
+		}
+	}
+	return devs
+}
+
+// nvidiaSmiList returns each card's "<name>, <pci bus>" line; empty
+// slice when nvidia-smi isn't installed or fails.
+func nvidiaSmiList(ctx context.Context) []string {
+	cmd := exec.CommandContext(ctx, "nvidia-smi", "-L")
+	out, err := cmd.Output()
+	if err != nil {
+		return nil
+	}
+	var lines []string
+	for _, l := range strings.Split(string(out), "\n") {
+		l = strings.TrimSpace(l)
+		if l != "" {
+			lines = append(lines, l)
+		}
+	}
+	return lines
+}
+
+func joinDevices(devs []string) string {
+	if len(devs) == 0 {
+		return ""
+	}
+	if len(devs) == 1 {
+		return devs[0]
+	}
+	return devs[0] + " (+" + strings.TrimSpace(formatCount(len(devs)-1, "more")) + ")"
+}