feat: Add Borg Backup support to simple LVM backup system

- Add LV → Borg and VG → Borg backup modes
- GUI: Borg settings panel with repo path, encryption, passphrase
- CLI: Enhanced script with Borg options (--new-repo, --encryption, --passphrase)
- Automatic repository initialization for new repos
- Support for all Borg encryption modes (none, repokey, keyfile)
- Mount snapshots temporarily for file-level Borg backups
- Comprehensive cleanup of snapshots and mount points
- Updated documentation and examples

Benefits:
- Deduplication and compression
- Strong encryption support
- Incremental backups capability
- Space-efficient storage
- Still maintains simple snapshot → backup → cleanup workflow

README.md

@@ -1,4 +1,4 @@
-# Enhanced Simple LVM Backup System
+# Enhanced Simple LVM Backup System with Borg Support
 
 A reliable, straightforward backup system for LVM-enabled Linux systems. Born from the need for simple, dependable backups without complex logic that can cause system issues.
 
@@ -6,22 +6,24 @@ A reliable, straightforward backup system for LVM-enabled Linux systems. Born fr
 
 **Simple is better.** This system does exactly three things:
 1. Create LVM snapshot
-2. Copy data with dd/pv  
+2. Copy data (dd/pv for raw, Borg for repositories)
 3. Clean up snapshot
 
 No complex migration logic, no fancy features that can break. Just reliable backups.
 
 ## Features
 
-### Three Backup Modes
+### Five Backup Modes
 
 - **LV → LV**: Update existing logical volume backups
 - **LV → Raw**: Create fresh backups on raw devices
 - **VG → Raw**: Clone entire volume groups with LVM metadata
+- **LV → Borg**: Backup logical volume to Borg repository (deduplicated, compressed, encrypted)
+- **VG → Borg**: Backup entire volume group to Borg repository
 
 ### Two Interfaces
 
-- **GUI**: `simple_backup_gui.py` - User-friendly interface
+- **GUI**: `simple_backup_gui.py` - User-friendly interface with Borg configuration
 - **CLI**: `enhanced_simple_backup.sh` - Command-line power user interface
 
 ## Quick Start
@@ -53,6 +55,15 @@ sudo ./enhanced_simple_backup.sh vg-to-raw internal-vg /dev/sdb
 sudo python3 simple_backup_gui.py
 ```
 
+**Borg repository backups:**
+```bash
+# Create new Borg repo and backup LV
+sudo ./enhanced_simple_backup.sh lv-to-borg /dev/internal-vg/root /path/to/borg/repo --new-repo --encryption repokey --passphrase mypass
+
+# Backup entire VG to existing repo
+sudo ./enhanced_simple_backup.sh vg-to-borg internal-vg /path/to/borg/repo --passphrase mypass
+```
+
 ## Files
 
 ### Core System
@@ -71,6 +82,7 @@ sudo python3 simple_backup_gui.py
 - Root access (`sudo`)
 - Python 3 + tkinter (for GUI)
 - `pv` command (optional, for progress display)
+- **Borg Backup** (for Borg modes): `sudo apt install borgbackup`
 
 ## Safety Features