Dgraph-related functionality, configuration, and benchmarks have been removed from the project. This streamlines the codebase to focus on supported backends, specifically eliminating Dgraph references in favor of Neo4j and other implementations. Version bumped to reflect the changes.
Replaced individual environment variable access with a unified `DatabaseConfig` struct for all database backends. This centralizes configuration management, reduces redundant code, and ensures all options are documented in `app/config/config.go`. Backward compatibility is maintained with default values and retained constructors.
