refactor&feat: Java -> Kotlin, better extension API; Javadoc support

[Vadym Yaroshchuk (y9vad9)]

Summary of Changes

This update introduces several structural improvements and feature additions to the Elide Gradle plugin, focusing on better integration, cleaner dependency management, and a more extensible CLI interface.

1. Removal of Version Catalog Module

• Removed the separate module used for managing Gradle Version Catalogs.
• Plugin now supports automated Elide CLI downloads based on a configured version (elide.settings.binary.version).
• Dependencies should now align with the Elide version specified via the plugin extension.

2. Javadoc Tooling via Elide

• Introduced support for invoking Elide's javadoc implementation.
• Uses the CLI through a platform-specific shim script.
• Configurable via elide.settings.features.javadocStrategy.

3. Javac Integration via JavaExec

• The previously used shim script for javac has been removed.
• Java compilation now uses JavaCompile.options.forkOptions.executable to invoke the Elide CLI directly.
• This approach is more robust and integrates better with Gradle’s compilation system.

4. elide.exec: Custom CLI Invocation Support

Added support for defining custom tasks that invoke the Elide CLI using the new elide.exec DSL.

Example: Custom Task Using elide.exec

val elideInfo = elide.exec(taskName = "elideInfo") {
    args("info")

    useInvocation { invocation ->
        invocation
            .withCapturedStdout()
            .consumeStderr { stream -> stream.forEach(logger::error) }
            .onException { e -> throw IllegalStateException("Failed to run `elide info`", e) }
            .onNonSuccessExitCode { exitCode -> error("Returned non-success exit code: $exitCode") }
            .onSuccess(logger::lifecycle)
    }

    debug = false
}

val elideVersion = elide.exec(taskName = "elideVersion") {
    args("--version")
}

• CLI verbosity (--debug, --verbose) is automatically inferred from plugin settings or Gradle log level.
• Captures and logs output and error streams.
• Optionally creates a marker file to support incremental builds.

---

5. Updated Elide Plugin Extension Configuration

The plugin extension (elide.settings) has been enhanced to support the following:

elide.settings {
    binary {
        silentMode = true
        strictVersionCheck = false

        useProjectBinary(
            version = "1.0.0-Beta07",
            downloadPath = layout.projectDirectory.dir(".elide").dir("bin"),
        )
    }

    features {
        enableElideInstall = true
        javacStrategy = ElideIntegrationStrategy.ELIDE_STRICT
        javadocStrategy = ElideIntegrationStrategy.NO_ELIDE
        enableTelemetry = false
    }

    diagnostics {
        debug = true
        verbose = false
    }
}

---

6. Dependency Resolution via Extension

Instead of using a centralized version catalog, dependencies are now accessible through the plugin-provided API:

dependencies {
    implementation(elide.runtime.core)
}

This ensures all dependencies are aligned with the configured Elide version and simplifies project setup.

[Vadym Yaroshchuk (y9vad9)]

Kotlin support was dropped due to inability to support it in a stable way. The usage of compiler internals make it very hard to be implemented. Requires more time to play around.

[Vadym Yaroshchuk (y9vad9)]

I still need to clean it up a little bit a test a little more, but for now I would love to receive initial feedback