Refactor build configs to use kotlin multiplatform plugin

[serpro69]

TODO

• test publishing
• cleanup buildSrc plugins
  • there's likely some dependencies that are duplicated which were there due to usage of shadow plugin
  • look over other stuff and clean it up
• update workflows
  • mvp: build and test from pr and merges to master; good-to-have: publishing snapshots from merges to master
• fix docs
  • snippets are broken

[Copilot]

Pull Request Overview

This PR refactors the build configurations to use the Kotlin Multiplatform plugin instead of the previous shadow jar approach. The changes modernize the build system, remove outdated dependencies, and consolidate build logic.

• Migrates from the shadow plugin approach to Kotlin Multiplatform plugin with proper source sets
• Updates build conventions and publishing configurations to support the new multiplatform structure
• Consolidates test execution and removes separate integration test tasks

Reviewed Changes

Copilot reviewed 37 out of 1267 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
core/build.gradle.kts	Migrates to Kotlin multiplatform with jvmMain/jvmTest source sets, removes shadow configuration
buildSrc/src/main/kotlin/*.gradle.kts	Updates build conventions to use multiplatform structure and modern publishing
cli-bot/build.gradle.kts	Updates dependencies and task configurations for new multiplatform setup
buildSrc/src/main/kotlin/utils/*	Adds new utility classes for build configuration and publishing
.github/workflows/*	Updates CI workflows to use new test commands and remove integration test tasks

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