Add support for running multiple nanobot instances with complete isolation:
- Add --config parameter to gateway command for custom config file path
- Implement set_config_path() in config/loader.py for dynamic config path
- Derive data directory from config file location (e.g., ~/.nanobot-xxx/)
- Update get_data_path() to use unified data directory from config loader
- Ensure cron jobs use instance-specific data directory
This enables running multiple isolated nanobot instances by specifying
different config files, with each instance maintaining separate:
- Configuration files
- Workspace (memory, sessions, skills)
- Cron jobs
- Logs and media
Example usage:
nanobot gateway --config ~/.nanobot-instance2/config.json --port 18791
