feat: add OpenSOSData MCP server

[OpenSOSData]

Adding OpenSOSData MCP server to the registry.

Motivation and Context

OpenSOSData provides real-time US business entity search across all
53 US jurisdictions - all 50 states, Washington DC, Puerto Rico, and
US Virgin Islands. Data is fetched live from official Secretary of State
portals at query time, not from a stale database. This fills a gap in
the registry - no business entity search MCP server currently exists.

Use cases: KYB compliance, due diligence, vendor verification, legal
research, and any workflow requiring confirmation of business registration
status.

How Has This Been Tested?

Tested end-to-end in Claude.ai (web), Claude Desktop, and Claude Code.
The remote MCP server at https://mcp.opensosdata.com/mcp is live in
production and has processed real user lookups. The npm package
@opensosdata/mcp-server v1.0.1 is published and working. Two external
users have signed up and used the service since launch.

Breaking Changes

None. This is a new server addition.

Types of changes

• New feature (non-breaking change which adds functionality)

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

• Remote MCP endpoint: https://mcp.opensosdata.com/mcp
• Documentation: https://opensosdata.com/mcp
• GitHub: https://github.com/OpenSOSData/opensosdata-mcp
• npm: @opensosdata/mcp-server
• Transport: Streamable HTTP
• Auth: Bearer token (API key from opensosdata.com)
• 6 tools, all readOnlyHint: true