feat: Enhanced simple LVM backup system

- Add 3 backup modes: LV→LV, LV→Raw, VG→Raw
- Simple GUI with mode selection and dynamic target lists
- Command-line version with clear mode support
- Enhanced drive listing with mode-specific options
- Minimal logic: just snapshot → copy → cleanup
- No complex migration features that cause system issues
- Supports refreshing existing backups and creating fresh ones

list_drives.sh

@@ -0,0 +1,86 @@
+#!/bin/bash
+
+# Enhanced script to list available backup sources and targets
+# Shows options for all three backup modes
+
+echo "=== Enhanced Simple LVM Backup - Available Options ==="
+echo ""
+
+echo "=== SOURCES ==="
+echo ""
+echo "Logical Volumes (for lv-to-lv and lv-to-raw modes):"
+echo "---------------------------------------------------"
+if command -v lvs >/dev/null 2>&1; then
+    echo "Path                     Size     VG Name"
+    echo "----------------------------------------"
+    lvs --noheadings -o lv_path,lv_size,vg_name | while read lv_path lv_size vg_name; do
+        printf "%-24s %-8s %s\n" "$lv_path" "$lv_size" "$vg_name"
+    done
+else
+    echo "LVM not available"
+fi
+
+echo ""
+echo "Volume Groups (for vg-to-raw mode):"
+echo "-----------------------------------"
+if command -v vgs >/dev/null 2>&1; then
+    echo "VG Name          Size     PV Count"
+    echo "----------------------------------"
+    vgs --noheadings -o vg_name,vg_size,pv_count | while read vg_name vg_size pv_count; do
+        printf "%-16s %-8s %s PVs\n" "$vg_name" "$vg_size" "$pv_count"
+    done
+else
+    echo "LVM not available"
+fi
+
+echo ""
+echo "=== TARGETS ==="
+echo ""
+echo "Existing Logical Volumes (for lv-to-lv mode):"
+echo "---------------------------------------------"
+if command -v lvs >/dev/null 2>&1; then
+    echo "Path                     Size     VG Name"
+    echo "----------------------------------------"
+    lvs --noheadings -o lv_path,lv_size,vg_name | while read lv_path lv_size vg_name; do
+        # Highlight external/backup VGs
+        if [[ "$vg_name" == *"migration"* ]] || [[ "$vg_name" == *"external"* ]] || [[ "$vg_name" == *"backup"* ]]; then
+            printf "%-24s %-8s %s (backup VG)\n" "$lv_path" "$lv_size" "$vg_name"
+        else
+            printf "%-24s %-8s %s\n" "$lv_path" "$lv_size" "$vg_name"
+        fi
+    done
+else
+    echo "LVM not available"
+fi
+
+echo ""
+echo "Raw Block Devices (for lv-to-raw and vg-to-raw modes):"
+echo "------------------------------------------------------"
+echo "Device     Size     Model"
+echo "-------------------------"
+lsblk -dno NAME,SIZE,MODEL | grep -E '^sd|^nvme' | while read name size model; do
+    printf "/dev/%-6s %-8s %s\n" "$name" "$size" "$model"
+done
+
+echo ""
+echo "=== USAGE EXAMPLES ==="
+echo ""
+echo "1. LV to LV (update existing backup):"
+echo "   sudo ./enhanced_simple_backup.sh lv-to-lv /dev/internal-vg/root /dev/backup-vg/root"
+echo ""
+echo "2. LV to Raw Device (fresh backup):"
+echo "   sudo ./enhanced_simple_backup.sh lv-to-raw /dev/internal-vg/root /dev/sdb"
+echo ""
+echo "3. Entire VG to Raw Device (complete clone):"
+echo "   sudo ./enhanced_simple_backup.sh vg-to-raw internal-vg /dev/sdb"
+echo ""
+echo "=== GUI VERSION ==="
+echo "   sudo python3 simple_backup_gui.py"
+echo ""
+echo "=== IMPORTANT NOTES ==="
+echo "- Always run as root (sudo)"
+echo "- lv-to-lv: Updates existing backup LV"
+echo "- lv-to-raw: Creates fresh backup, overwrites target device"
+echo "- vg-to-raw: Clones entire VG including LVM metadata"
+echo "- Make sure target devices are unmounted before backup"
+echo ""