test: Refactor test utilities, fix conformance (#476)

# Refactor test utilities, fix conformance

- Add `test-utils` module to streamline test cases
- Rename module `kotlin-sdk-test` -> `integration-test`
- Move test utilities for managing processes, ports, and TypeScript
execution logic
- Make conformance tests work by specifying conformance package version
(0.1.8)

## Motivation and Context
Reuse test infrastructure code, resurrect conformance tests

## How Has This Been Tested?
CI, locally

## Breaking Changes
No

## Types of changes
- [x] Bug fix (non-breaking change which fixes an issue)
- [x] Tests update

## Checklist
<!-- Go over all the following points, and put an `x` in all the boxes
that apply. -->
- [x] I have read the [MCP
Documentation](https://modelcontextprotocol.io)
- [x] My code follows the repository's style guidelines
- [x] New and existing tests pass locally
- [ ] I have added appropriate error handling
- [ ] I have added or updated documentation as needed

conformance-test/build.gradle.kts

@@ -7,6 +7,7 @@ plugins {
 dependencies {
     testImplementation(project(":kotlin-sdk"))
     testImplementation(kotlin("test"))
+    testImplementation(project(":test-utils"))
     testImplementation(libs.kotlin.logging)
     testImplementation(libs.ktor.client.cio)
     testImplementation(libs.ktor.server.cio)

conformance-test/src/test/kotlin/io/modelcontextprotocol/kotlin/sdk/conformance/ConformanceTest.kt

@@ -17,6 +17,8 @@ import kotlin.properties.Delegates
 
 private val logger = KotlinLogging.logger {}
 
+private const val CONFORMANCE_VERSION = "0.1.8"
+
 enum class TransportType {
     SSE,
     WEBSOCKET,
@@ -215,7 +217,7 @@ class ConformanceTest {
                 val serverUrl = "http://127.0.0.1:$serverPort/mcp"
                 ProcessBuilder(
                     "npx",
-                    "@modelcontextprotocol/conformance",
+                    "@modelcontextprotocol/conformance@$CONFORMANCE_VERSION",
                     "server",
                     "--url",
                     serverUrl,
@@ -230,7 +232,7 @@ class ConformanceTest {
                 val serverUrl = "ws://127.0.0.1:$serverPort/ws"
                 ProcessBuilder(
                     "npx",
-                    "@modelcontextprotocol/conformance",
+                    "@modelcontextprotocol/conformance@$CONFORMANCE_VERSION",
                     "server",
                     "--url",
                     serverUrl,
@@ -274,7 +276,7 @@ class ConformanceTest {
 
         val processBuilder = ProcessBuilder(
             "npx",
-            "@modelcontextprotocol/conformance",
+            "@modelcontextprotocol/conformance@$CONFORMANCE_VERSION",
             "client",
             "--command",
             clientCommand.joinToString(" "),