feat(webui): add Install to Disk page

Expose the existing bee-install script through the web UI:
- platform/install.go: remove USB exclusion, add SizeBytes/MountedParts
  fields, add MinInstallBytes()/DiskWarnings() safety checks (size,
  mounted partitions, toram+low-RAM warning)
- webui: add GET /api/install/disks, POST /api/install/run,
  GET /api/install/stream endpoints
- webui: add Install to Disk page with disk table, warning badges,
  device-name confirmation gate, SSE progress terminal, reboot button

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

audit/internal/platform/install.go

@@ -3,6 +3,7 @@ package platform
 import (
 	"context"
 	"fmt"
+	"os"
 	"os/exec"
 	"strconv"
 	"strings"
@@ -10,13 +11,17 @@ import (
 
 // InstallDisk describes a candidate disk for installation.
 type InstallDisk struct {
-	Device string // e.g. /dev/sda
-	Model  string
-	Size   string // human-readable, e.g. "500G"
+	Device      string   // e.g. /dev/sda
+	Model       string
+	Size        string   // human-readable, e.g. "500G"
+	SizeBytes   int64    // raw byte count from lsblk
+	MountedParts []string // partition mount points currently active
 }
 
+const squashfsPath = "/run/live/medium/live/filesystem.squashfs"
+
 // ListInstallDisks returns block devices suitable for installation.
-// Excludes USB drives and the current live boot medium.
+// Excludes the current live boot medium but includes USB drives.
 func (s *System) ListInstallDisks() ([]InstallDisk, error) {
 	out, err := exec.Command("lsblk", "-dn", "-o", "NAME,MODEL,SIZE,TYPE,TRAN").Output()
 	if err != nil {
@@ -33,7 +38,6 @@ func (s *System) ListInstallDisks() ([]InstallDisk, error) {
 			continue
 		}
 		// Last field: TRAN, second-to-last: TYPE, third-to-last: SIZE
-		tran := fields[len(fields)-1]
 		typ := fields[len(fields)-2]
 		size := fields[len(fields)-3]
 		name := fields[0]
@@ -42,24 +46,58 @@ func (s *System) ListInstallDisks() ([]InstallDisk, error) {
 		if typ != "disk" {
 			continue
 		}
-		if strings.EqualFold(tran, "usb") {
-			continue
-		}
 
 		device := "/dev/" + name
 		if device == bootDev {
 			continue
 		}
 
+		sizeBytes := diskSizeBytes(device)
+		mounted := mountedParts(device)
+
 		disks = append(disks, InstallDisk{
-			Device: device,
-			Model:  strings.TrimSpace(model),
-			Size:   size,
+			Device:       device,
+			Model:        strings.TrimSpace(model),
+			Size:         size,
+			SizeBytes:    sizeBytes,
+			MountedParts: mounted,
 		})
 	}
 	return disks, nil
 }
 
+// diskSizeBytes returns the byte size of a block device using lsblk.
+func diskSizeBytes(device string) int64 {
+	out, err := exec.Command("lsblk", "-bdn", "-o", "SIZE", device).Output()
+	if err != nil {
+		return 0
+	}
+	n, _ := strconv.ParseInt(strings.TrimSpace(string(out)), 10, 64)
+	return n
+}
+
+// mountedParts returns a list of "<part> at <mountpoint>" strings for any
+// mounted partitions on the given device.
+func mountedParts(device string) []string {
+	out, err := exec.Command("lsblk", "-n", "-o", "NAME,MOUNTPOINT", device).Output()
+	if err != nil {
+		return nil
+	}
+	var result []string
+	for _, line := range strings.Split(strings.TrimSpace(string(out)), "\n") {
+		fields := strings.Fields(line)
+		if len(fields) < 2 {
+			continue
+		}
+		mp := fields[1]
+		if mp == "" || mp == "[SWAP]" {
+			continue
+		}
+		result = append(result, "/dev/"+strings.TrimLeft(fields[0], "└─├─")+" at "+mp)
+	}
+	return result
+}
+
 // findLiveBootDevice returns the block device backing /run/live/medium (if any).
 func findLiveBootDevice() string {
 	out, err := exec.Command("findmnt", "-n", "-o", "SOURCE", "/run/live/medium").Output()
@@ -79,6 +117,80 @@ func findLiveBootDevice() string {
 	return "/dev/" + strings.TrimSpace(string(out2))
 }
 
+// MinInstallBytes returns the minimum recommended disk size for installation:
+// squashfs size × 1.5 to allow for extracted filesystem and bootloader.
+// Returns 0 if the squashfs is not available (non-live environment).
+func MinInstallBytes() int64 {
+	fi, err := os.Stat(squashfsPath)
+	if err != nil {
+		return 0
+	}
+	return fi.Size() * 3 / 2
+}
+
+// toramActive returns true when the live system was booted with toram.
+func toramActive() bool {
+	data, err := os.ReadFile("/proc/cmdline")
+	if err != nil {
+		return false
+	}
+	return strings.Contains(string(data), "toram")
+}
+
+// freeMemBytes returns MemAvailable from /proc/meminfo.
+func freeMemBytes() int64 {
+	data, err := os.ReadFile("/proc/meminfo")
+	if err != nil {
+		return 0
+	}
+	for _, line := range strings.Split(string(data), "\n") {
+		if strings.HasPrefix(line, "MemAvailable:") {
+			fields := strings.Fields(line)
+			if len(fields) >= 2 {
+				n, _ := strconv.ParseInt(fields[1], 10, 64)
+				return n * 1024 // kB → bytes
+			}
+		}
+	}
+	return 0
+}
+
+// DiskWarnings returns advisory warning strings for a disk candidate.
+func DiskWarnings(d InstallDisk) []string {
+	var w []string
+	if len(d.MountedParts) > 0 {
+		w = append(w, "has mounted partitions: "+strings.Join(d.MountedParts, ", "))
+	}
+	min := MinInstallBytes()
+	if min > 0 && d.SizeBytes > 0 && d.SizeBytes < min {
+		w = append(w, fmt.Sprintf("disk may be too small (need ≥ %s, have %s)",
+			humanBytes(min), humanBytes(d.SizeBytes)))
+	}
+	if toramActive() {
+		sqFi, err := os.Stat(squashfsPath)
+		if err == nil {
+			free := freeMemBytes()
+			if free > 0 && free < sqFi.Size()*2 {
+				w = append(w, "toram mode — low RAM, extraction may be slow or fail")
+			}
+		}
+	}
+	return w
+}
+
+func humanBytes(b int64) string {
+	const unit = 1024
+	if b < unit {
+		return fmt.Sprintf("%d B", b)
+	}
+	div, exp := int64(unit), 0
+	for n := b / unit; n >= unit; n /= unit {
+		div *= unit
+		exp++
+	}
+	return fmt.Sprintf("%.1f %cB", float64(b)/float64(div), "KMGTPE"[exp])
+}
+
 // InstallToDisk runs bee-install <device> <logfile> and streams output to logFile.
 // The context can be used to cancel.
 func (s *System) InstallToDisk(ctx context.Context, device string, logFile string) error {
@@ -92,14 +204,11 @@ func InstallLogPath(device string) string {
 	return "/tmp/bee-install" + safe + ".log"
 }
 
-// DiskLabel returns a display label for a disk.
+// Label returns a display label for a disk.
 func (d InstallDisk) Label() string {
 	model := d.Model
 	if model == "" {
 		model = "Unknown"
 	}
-	sizeBytes, err := strconv.ParseInt(strings.TrimSuffix(d.Size, "B"), 10, 64)
-	_ = sizeBytes
-	_ = err
 	return fmt.Sprintf("%s  %s  %s", d.Device, d.Size, model)
 }