Add Kotlin-in-Gradle-project skill

[e5l]

Summary

• Adds kotlin-tooling-add-kotlin-to-gradle-project skill that guides configuring Kotlin in existing Java Gradle projects
• Uses kotlin("jvm") plugin with jvmToolchain and kotlin("test") for minimal, clean mixed Java-Kotlin builds
• Includes analysis script (scripts/analyze-gradle-project.sh), verification checklist, and compiler plugins reference (Spring, JPA, serialization)
• Companion to the Maven equivalent in Add Kotlin-in-Maven-project skill #8

What the skill covers

• Adding kotlin("jvm") plugin (both direct version and version catalog approaches)
• Configuring jvmToolchain to match the project's Java version
• Adding kotlin("test") dependency (auto-detects JUnit 5 from useJUnitPlatform())
• Directory structure options (co-located .kt alongside .java vs separate kotlin/ dirs)
• Multi-module Gradle projects (apply false + per-module, convention plugins, subprojects block)
• Groovy DSL syntax
• Common issues and troubleshooting

Test plan

• Analysis script correctly detects unconfigured project (initial/) and configured project (complete/)
• Skill agent test running against kotlin-junit-sample initial/ project (in progress)
• CI validation should pass (kotlin-tooling-* naming convention)

🤖 Generated with Claude Code

[Tapchicoma]

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