Add Kotlin language support

[Copilot]

Implements Kotlin code analysis to enable graph representation of Kotlin codebases alongside existing Python and Java support.

Changes

• api/analyzers/kotlin/analyzer.py: New KotlinAnalyzer implementing AbstractAnalyzer

  • Parses classes, interfaces, objects (singletons), functions, and methods
  • Extracts inheritance, interface implementation, function calls, parameters, return types
  • Supports KDoc documentation extraction

• api/analyzers/source_analyzer.py:

  • Registered .kt and .kts extensions with KotlinAnalyzer
  • Added Kotlin to file discovery in analyze_sources()
  • Integrated language server placeholder (uses NullLanguageServer pending LSP configuration)

• pyproject.toml: Added tree-sitter-kotlin ^1.1.0 dependency

• README.md: Updated supported languages from "Python and C" to "Python, Java, and Kotlin"

Example

interface Task {
    fun execute()
}

class WorkerTask(val name: String) : Task {
    override fun execute() {
        println("Executing: $name")
    }
    
    fun abort(): WorkerTask {
        return this
    }
}

object TaskManager {
    fun createTask(name: String) = WorkerTask(name)
}

The analyzer extracts entities (Interface: Task, Class: WorkerTask, Object: TaskManager) and relationships (IMPLEMENTS, CALLS, RETURNS) to build the code graph.

Original prompt

---

This section details on the original issue you should resolve

<issue_title>Add support for Kotlin</issue_title>
<issue_description>Would appreciate. I believe there is nothing yet on the field with kotlin support.</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes Add support for Kotlin #93

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Project	Deployment	Preview	Comments	Updated (UTC)
code-graph-backend	Ready	Preview	Comment	Nov 2, 2025 8:37am

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