Fixes to project creation and completion

refactor: modularize plugin architecture and improve code organization

- Split monolithic plugin into separate modules for API, UI, handlers, and models
- Moved API client functionality into dedicated RavencolonialAPIClient class
- Created UIManager class to handle all UI-related operations
- Extracted journal event handling logic into JournalEventHandler class
- Implemented PluginConfig module for centralized configuration and logging
- Simplified main plugin class by delegating responsibilities to specialize