feat(truecalci): add truecalci deterministic compute server

[truecalci]

Description

Adds the TrueCalci deterministic calculation engine as a Streamable HTTP MCP server located at src/truecalci/server.json.

TrueCalci provides 24 zero-hallucination mathematical and statutory calculation engines (Income tax brackets, mortgage PITI/PMI, contractor parity, compound schedules, and engineering formulas) executed at Cloudflare Edge.

Server Details

• Server: TrueCalci
• Repository: https://github.com/truecalci-official/truecalci
• Homepage: https://truecalci.com
• Transport: Streamable HTTP (https://truecalci.com/api/v1/mcp)
• Engines: 24 Deterministic Tools

Motivation and Context

AI models frequently hallucinate compound interest schedules, tax brackets, and floating-point math. TrueCalci provides deterministic, IEEE-754 precision math tools to prevent financial and arithmetic hallucinations in AI agents.

How Has This Been Tested?

• Verified via JSON-RPC 2.0 handshake (initialize, tools/list, tools/call).
• Validated live on Claude Desktop and Cursor IDE over Streamable HTTP.
• Automated unit test suite passing locally and deployed to Cloudflare Edge.

Types of changes

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

Checklist

• I have read the MCP Protocol Documentation
• My changes follows MCP security best practices
• I have updated the server's README accordingly
• I have tested this with an LLM client
• My code follows the repository's style guidelines
• New and existing tests pass locally
• I have added appropriate error handling
• I have documented all environment variables and configuration options