feat: x3-backup v1.0.0 initial release

GTK3 backup/snapshot tool using rsync backend.

Features:
- rsync-based snapshots with hardlink delta for space efficiency
- Snapshot sidebar with date-sorted list
- Full file browser with permissions display (name, size, perms, mtime)
- Right-click context menu: Restore file/dir with sudo prompt
- System tray icon: backup status, context menu (show/backup/settings/quit)
- Menu system: File, Backup, System, Help
- Settings dialog: backup destination, source path, retention, exclusions
- Cronjob management: install/remove scheduled backups
- Live Log tab: real-time rsync output during backup
- History Log tab: full log file viewer with color-coded entries
- System Backup mode: full root filesystem backup
- System Restore mode: restore entire system from snapshot
- CLI mode: --backup, --system-backup for cron/headless use
- /mnt always excluded from backups
- Preserves permissions, ACLs, xattrs (-aAX flags)
- Log file: ~/.config/x3-backup/x3-backup.log
- Config: ~/.config/x3-backup/settings.json
- uninstall.sh for clean removal

uninstall.sh

@@ -0,0 +1,36 @@
+#!/bin/bash
+set -e
+
+echo "=== x3-Backup Uninstall ==="
+
+# Remove installed files
+echo "Removing installed files..."
+if [ -f /usr/local/bin/x3-backup ]; then
+    sudo rm -f /usr/local/bin/x3-backup
+    echo "  Removed /usr/local/bin/x3-backup"
+fi
+
+if [ -f /usr/local/share/applications/x3-backup.desktop ]; then
+    sudo rm -f /usr/local/share/applications/x3-backup.desktop
+    echo "  Removed desktop file"
+fi
+
+if [ -f /usr/local/share/icons/hicolor/256x256/apps/x3-backup.png ]; then
+    sudo rm -f /usr/local/share/icons/hicolor/256x256/apps/x3-backup.png
+    echo "  Removed icon"
+fi
+
+# Remove cronjob
+echo "Removing cronjob..."
+crontab -l 2>/dev/null | grep -v 'x3-backup-auto' | crontab - 2>/dev/null || true
+echo "  Cronjob removed"
+
+# Ask about config and data
+echo ""
+echo "Config and backup data in ~/.config/x3-backup/ were NOT removed."
+echo "To remove config:  rm -rf ~/.config/x3-backup"
+echo ""
+echo "Backup snapshots were NOT removed."
+echo "To remove backups: check your configured backup destination"
+echo ""
+echo "Done."