Improve project structure and migrate to Gradle version catalog

[nakamura-to]

Summary

• Simplified project structure by removing the codegen-test module and moving its functionality to the root project
• Migrated dependency management to Gradle version catalog for centralized version control
• Improved maintainability and reduced complexity of the build configuration

Changes

1. Project Structure Simplification

• Removed the separate codegen-test module
• Moved integration test configuration to the root build.gradle.kts
• Moved SQL initialization script and templates to the root project
• This reduces the number of Gradle modules from 2 to 1, simplifying the build

2. Gradle Version Catalog Migration

• Created gradle/libs.versions.toml to centralize all dependency versions
• Updated both root and codegen module to use the version catalog
• Removed hardcoded version strings from build files
• Configured the codegen module (included build) to reference the parent's version catalog

Benefits

• Simpler structure: One less module to maintain
• Centralized versions: All dependency versions in one place
• Better IDE support: Version catalog provides autocomplete and navigation
• Easier updates: Change versions in one location
• Consistent dependencies: Ensures version alignment across modules

Test plan

• Build passes with ./gradlew clean build
• Code formatting applied with ./gradlew spotlessApply
• Integration tests can be run with ./gradlew domaCodeGenJavaAll build
• Plugin can be published (structure maintained for com.gradle.plugin-publish)

🤖 Generated with Claude Code