Light Wallet Upgrades, Ubuntu 24 Support

[blondfrogs]

Watchonly Mode Improvements

Performance Enhancements

• 10x faster initial sync for first watchonly address (reduced from 20+ minutes to ~2 minutes)
• Enhanced caching system with crash recovery support using checkpoints for safer syncing
• Improved database structure with updated database keys

New RPC Calls

backupwatchonlyaddresses

Exports all watchonly addresses with their configuration data for server providers.

Features:

• Exports scan secrets, spend public keys, and height information
• Supports optional file output to handle large datasets without terminal buffer issues
• Returns JSON response or writes to file based on parameters
• Note: Contains private keys (scan secrets) - keep backups secure!

Usage:

# Export to JSON response
backupwatchonlyaddresses

# Export to file
backupwatchonlyaddresses "/path/to/backup.json"

importwatchonlybackup

Imports watchonly addresses from backup created by backupwatchonlyaddresses.

Features:
- Restores watchonly addresses on fresh servers without re-importing UTXOs
- Follows same import pattern as importlightwalletaddress for consistency
- Supports both direct JSON array input and file paths
- Automatically detects input type (file path vs. JSON data)

Usage:
# Import from file
importwatchonlybackup "/path/to/backup.json"

# Import from JSON array
importwatchonlybackup '[{"scan_secret":"...", ...}]'

removewatchonlyaddress

Removes a watch-only address from monitoring while preserving transaction data in the database.

compactwatchonlydb

Compacts the watchonly database for optimized storage and performance.

Other Improvements

- Light wallet ring size support: Expanded compatibility to work with more ring sizes
- Ubuntu 24.04 build fixes: Resolved compatibility issues for building on Ubuntu 24.04
- Cleaned up RPC interface: Removed obsolete test parameters from getwatchonlytxes RPC call

---
Backup Data Format

The backup contains only address configuration (scan secrets, spend pubkeys, scan heights) - not transaction/UTXO data. This allows fresh servers to resync from the
blockchain to rebuild their watchonly transaction database.

[seanPhill]

utACK

[seanPhill]

utACK

[seanPhill]

utACK

[seanPhill]

utACK

[seanPhill]

utACK