feat: task queue, UI overhaul, burn tests, install-to-RAM

- Task queue: all SAT/audit jobs enqueue and run one-at-a-time;
  tasks persist past page navigation; new Tasks page with cancel/priority/log stream
- UI: consolidate nav (Validate, Burn, Tasks, Tools); Audit becomes modal;
  Dashboard hardware summary badges + split metrics charts (load/temp/power);
  Tools page consolidates network, services, install, support bundle
- AMD GPU: acceptance test and stress burn cards; GPU presence API greys
  out irrelevant SAT cards automatically
- Burn tests: Memory Stress (stress-ng --vm), SAT Stress (stressapptest)
- Install to RAM: copies squashfs to /dev/shm, re-associates loop devices
  via LOOP_CHANGE_FD ioctl so live media can be ejected
- Charts: relative time axis (0 = now, negative left)
- memtester: LimitMEMLOCK=infinity in bee-web.service; empty output → UNSUPPORTED
- SAT overlay applied dynamically on every /audit.json serve
- MIME panic guard for LiveCD ramdisk I/O errors
- ISO: add memtest86+, stressapptest packages; memtest86+ GRUB entry;
  disable screensaver/DPMS in bee-openbox-session
- Unknown SAT status severity = 1 (does not override OK)

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

audit/internal/platform/network.go

@@ -131,6 +131,25 @@ func (s *System) SetStaticIPv4(cfg StaticIPv4Config) (string, error) {
 	return out.String(), nil
 }
 
+// SetInterfaceState brings a network interface up or down.
+func (s *System) SetInterfaceState(iface string, up bool) error {
+	state := "down"
+	if up {
+		state = "up"
+	}
+	return exec.Command("ip", "link", "set", "dev", iface, state).Run()
+}
+
+// GetInterfaceState returns true if the interface is UP.
+func (s *System) GetInterfaceState(iface string) (bool, error) {
+	raw, err := os.ReadFile(fmt.Sprintf("/sys/class/net/%s/operstate", iface))
+	if err != nil {
+		return false, err
+	}
+	state := strings.TrimSpace(string(raw))
+	return state == "up", nil
+}
+
 func listInterfaceNames() ([]string, error) {
 	raw, err := exec.Command("ip", "-o", "link", "show").Output()
 	if err != nil {