JBAI-13681 Implement OpenRouter clients and prompt executor

[e5l]

Fix part of JBAI-13681 Implement Gemini, LightLLM, OpenRouter clients and prompt executors.

[Copilot]

Pull Request Overview

This PR implements support for OpenRouter clients and adds a prompt executor for the new provider.

• Added a new include in settings.gradle.kts for the OpenRouter client.
• Introduced the OpenRouter provider in LLMProvider.kt and updated LLMCapability.kt with a Vision capability.
• Added tests and client implementations for OpenRouter in JVM, JS, and common modules.

Reviewed Changes

Copilot reviewed 13 out of 13 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
settings.gradle.kts	Added module include for the OpenRouter client.
LLMProvider.kt	Added OpenRouter provider entry.
LLMCapability.kt	Added a Vision capability entry.
SimplePromptExecutors.kt	Provided a new executor for OpenRouter.
build.gradle.kts (prompt-executor-llms-all)	Added dependency for the OpenRouter client.
OpenRouterDirectClientTest.kt	Added integration tests for OpenRouter client functionality.
JvmEngineProvider.kt & OpenRouterDirectLLMClient.js.kt	Provided platform-specific engine support for OpenRouter client.
OpenRouterModels.kt	Defined various OpenRouter-based LLM models.
build.gradle.kts (openrouter-client)	Configured multiplatform dependencies and publishing for the new client.
CLAUDE.md	Added documentation specific to working with code in this repository.

Comments suppressed due to low confidence (1)

prompt/prompt-executor/prompt-executor-clients/prompt-executor-openrouter-client/src/commonMain/kotlin/ai/jetbrains/code/prompt/executor/clients/openrouter/OpenRouterModels.kt:57

• [nitpick] The model identifier 'GPT4o' may be ambiguous; consider renaming it to a more descriptive name (e.g., 'GPT4Alternate') to improve clarity.

val GPT4o = LLModel(

[e5l]

Using the free model for tests. Please consider adding an OpenRouter token on CI