Refactor encrypt-config Command Implementation

The encrypt-config command in nifi-toolkit-encrypt-config supports protection of sensitive properties in multiple application configuration files. The current implementation supports NiFi and NiFi Registry with similar capabilities.

The existing implementation is written in Groovy and includes some amount of duplication between operating modes.

The command supports capabilities unique to NiFi for protection for specific property values in application properties and flow configuration files.

The encrypt-config command components should be refactored using the picocli framework to streamline the implementation. This refactoring should focus on supporting existing command arguments to provide compatibility with existing usage patterns. Separate efforts could consider a redesigned approach with different arguments and sub-commands, but refactoring the current implementation will provide a more maintainable solution.