Replace multiple USB scripts with single interactive version

Consolidated all USB setup functionality into one script:
- setup_usb.sh (formerly setup_usb_interactive.sh)

Removed deprecated scripts:
- setup_usb_automount.sh
- setup_usb_final.sh
- old setup_usb.sh

New setup_usb.sh features:
- Interactive menu-driven interface
- Scans for all connected USB drives automatically
- Displays device info (label, size, UUID, filesystem)
- Let user select which drives to auto-mount
- Custom mount point names (usb0, usb1, backup, etc.)
- Creates systemd .mount and .automount units
- Handles cleanup and conflict resolution
- Proper permissions (uid/gid)
- Works with drives plugged in after boot

Updated README.md documentation to reflect new workflow.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

README.md

@@ -391,14 +391,16 @@ Automatically backup all recordings and greeting files to USB drives:
 
 **Automated Setup (Easiest):**
 ```bash
-# Run the USB setup script
+# Run the interactive USB setup script
 sudo ./setup_usb.sh
 ```
 This interactive script will:
-- Detect your USB devices
-- Mount them with proper user permissions
-- Test write access
-- Optionally add to /etc/fstab for auto-mounting
+- Scan for all connected USB drives
+- Let you select which drives to auto-mount
+- Choose custom mount point names (e.g., usb0, usb1, backup)
+- Create systemd auto-mount units
+- Handle permissions automatically (uid/gid)
+- Work even when USB drives are plugged in after boot
 
 **Option 1: Mount with user permissions (Recommended)**
 ```bash
@@ -461,7 +463,7 @@ wedding-phone/
 ├── test_complete.py           # Audio testing script
 ├── configure_hifiberry.sh     # HiFiBerry DAC+ADC setup script
 ├── install_service.sh         # Systemd service installer (interactive)
-├── setup_usb.sh               # USB drive setup with permissions (interactive)
+├── setup_usb.sh               # Interactive USB auto-mount setup (systemd)
 ├── wedding-phone.service      # Systemd service file template
 ├── Makefile                   # Make commands (start, test, sync, clean)
 ├── config.example.json       # Example configuration (copy to config.json)