chore(docs): add highlightai to client list

[umuthopeyildirim]

I added HighlightAI to the clients list with feature support and detailed description.

Motivation and Context

Adding HighlightAI to the MCP clients list to showcase another implementation and help users discover available MCP-compatible applications. HighlightAI provides unique features like local audio transcription and screen capture with MCP integration.

How Has This Been Tested?

Verified HighlightAI's MCP implementation in production
Tested MCP server integration with environment variables
Validated feature matrix accuracy

Breaking Changes

None - This is an additive change to documentation only.

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

HighlightAI also maintains an open source MCP bundler and public registry of MCP servers that other clients can use.
Bundler: https://github.com/highlight-ing/mcp-bundler
Registry: https://mcpservers.com/