WIP

Currently not working:

• Deserializing authentication with Spring Boot.

Problem

Our current Java integration lacks several configuration properties and doesn’t consistently use type-safe structures.

Solution

This PR introduces several improvements:

• Added enums for specific types (e.g., ScalarTheme) to ensure stronger type safety.
• Auto-generated ScalarClient and ScalarTarget enums (like in our .NET integration).
• Refactored the structure to align (mostly) with the .NET integration.
• Added a AbstractScalarController class as a base class for other controllers.
• Added a ConfigureProperties() method in AbstractScalarController, allowing configuration updates before JSON serialization.
• Replaced manual string construction with a proper JSON serializer.
• Update the Renovate configuration to disable certain updates for the Java integration.

⚠️ There are some breaking changes:

The following string-based properties have been replaced with enum-based properties:

• theme field and getTheme()/setTheme() methods
• layout field and getLayout()/setLayout() methods
• documentDownloadType field and getDocumentDownloadType()/setDocumentDownloadType() methods

The ScalarSource class has been moved from a nested class in ScalarProperties to a standalone class in the config package:

• Old location: com.scalar.maven.webjar.ScalarProperties.ScalarSource
• New location: com.scalar.maven.webjar.config.ScalarSource

Checklist

I've gone through the following:

• I've added an explanation why this change is needed.
• I've added a changeset (pnpm changeset).
• I've added tests for the regression or new feature.
• I've updated the documentation.