New type filecontent

[cthulhu-tww]

Motivation and Context

When the MCP server responds to various files, ImageContent is not enough to meet my requirements. To be precise, I would prefer a response type and file name that theoretically supports various files. So I added FileContent, although some features have similarities with ImageContent, FileContent may be more comprehensive.

How Has This Been Tested?

There is a unit test, and I have integrated this modification into our system

Breaking Changes

It should not affect the existing functions

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation update

Checklist

• I have read the MCP Documentation
• My code follows the repository's style guidelines
• New and existing tests pass locally
• I have added appropriate error handling
• I have added or updated documentation as needed

Additional context

[ihrpr]

Thank you for your contribution!
This PR introduces a FileContent type that is not part of the MCP protocol specification. Adding a non-standard content type would break protocol compliance and interoperability with other MCP implementations.