feat!: SEP-1577 sampling with tools (#718)

Implements SEP-1577 sampling With tools

closes #409 

## How Has This Been Tested?
unit + integration 

## Breaking Changes
- binary changes
- MediaContent -> SamplingMessageContent
- 

## Types of changes
- [ ] Bug fix (non-breaking change which fixes an issue)
- [x] New feature (non-breaking change which adds functionality)
- [x] Breaking change (fix or feature that would cause existing
functionality to change)
- [ ] Documentation update

## Checklist
- [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
- [x] I have added appropriate error handling
- [x] I have added or updated documentation as needed

conformance-test/src/main/kotlin/io/modelcontextprotocol/kotlin/sdk/conformance/ConformanceTools.kt

@@ -176,11 +176,11 @@ fun Server.registerConformanceTools() {
             CreateMessageRequest(
                 CreateMessageRequestParams(
                     maxTokens = 10000,
-                    messages = listOf(SamplingMessage(Role.User, TextContent(prompt))),
+                    messages = listOf(SamplingMessage(Role.User, listOf(TextContent(prompt)))),
                 ),
             ),
         )
-        CallToolResult(listOf(TextContent(result.content.toString())))
+        CallToolResult(listOf(TextContent(result.content.joinToString("\n") { it.toString() })))
     }
 
     // 9. Elicitation