v0.10.0: Phase B — Storage Management UI Polish & Health Severity Fix

- Health severity fix: mount-point check downgraded from issue (FAIL) to warning (WARN)
- All storage health messages translated to Hungarian
- Success flash messages for all storage operations
- Edit storage path labels (inline edit UI + backend)
- App details per storage path on settings page (expandable list with names + sizes)
- Storage badge on stacks page showing which storage each app uses
- Deploy dropdown with free space display and low-space warning (<20%)
- Filesystem & disk info on settings page (ext4/btrfs, device, model via findmnt)
- Backup page storage context with per-app storage label badges

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

controller/internal/system/mounts_linux.go

@@ -5,6 +5,7 @@ package system
 import (
 	"fmt"
 	"os"
+	"os/exec"
 	"path/filepath"
 	"strings"
 	"syscall"
@@ -90,3 +91,52 @@ func formatGB(gb float64) string {
 	}
 	return fmt.Sprintf("%.1f GB", gb)
 }
+
+// FSInfo holds filesystem type, device, and disk model info.
+type FSInfo struct {
+	FSType string // "ext4", "btrfs"
+	Device string // "/dev/sda1"
+	Model  string // "WD Elements 25A2" (best-effort from sysfs)
+}
+
+// GetFSInfo returns filesystem info for a path using findmnt, or nil on error.
+func GetFSInfo(path string) *FSInfo {
+	out, err := exec.Command("findmnt", "-n", "-o", "SOURCE,FSTYPE", "--target", path).Output()
+	if err != nil {
+		return nil
+	}
+	fields := strings.Fields(strings.TrimSpace(string(out)))
+	if len(fields) < 2 {
+		return nil
+	}
+	info := &FSInfo{
+		Device: fields[0],
+		FSType: fields[1],
+	}
+	// Try to get disk model from sysfs
+	info.Model = diskModel(info.Device)
+	return info
+}
+
+// diskModel reads the disk model from /sys/block/<dev>/device/model.
+func diskModel(device string) string {
+	// /dev/sda1 → sda, /dev/nvme0n1p1 → nvme0n1
+	base := filepath.Base(device)
+	// Strip partition number: sda1 → sda, nvme0n1p1 → nvme0n1
+	disk := base
+	if strings.HasPrefix(base, "nvme") {
+		// nvme0n1p1 → find last 'p' followed by digits
+		if idx := strings.LastIndex(base, "p"); idx > 4 {
+			disk = base[:idx]
+		}
+	} else {
+		// sda1 → sda: strip trailing digits
+		disk = strings.TrimRight(base, "0123456789")
+	}
+	modelPath := "/sys/block/" + disk + "/device/model"
+	data, err := os.ReadFile(modelPath)
+	if err != nil {
+		return ""
+	}
+	return strings.TrimSpace(string(data))
+}