feat(mcp): build and publish CI/CD pipeline for @contextos/mcp package

[kok-o]

Problem Statement

In \�2.0.0, the ContextOS MCP server and execution runtime were decoupled from the core \contextos-agents\ package and moved to \contextos-mcp/\ to keep the core compiler lightweight and zero-dependency.

While the code is fully built, tested (Vitest), and verified on Ubuntu, macOS, and Windows in CI, there is currently no dedicated automated workflow to publish @contextos/mcp\ to npm upon release tags (e.g. @contextos/mcp@0.3.1\ or \mcp-v0.3.1).

Objective

Provide an automated GitHub Actions release workflow that packages, tests, and publishes @contextos/mcp\ under the @contextos\ npm scope.

Scope of Work

1. GitHub Actions Workflow (.github/workflows/publish-mcp.yml):
   • Trigger on release or tag pattern (e.g. @contextos/mcp@\ or \mcp-v).
   • Run typecheck, Biome linter, and Vitest suite across matrix.
   • Verify tarball packaging (
     pm pack --dry-run).
   • Publish to npm with public access using \NPM_TOKEN.
2. Version & Tarball Verification:
   • Ensure \dist/\ and binary assets are properly built and bundled prior to publishing.
   • Verify that package version in \contextos-mcp/package.json\ matches release tag.

Acceptance Criteria

• Dedicated workflow .github/workflows/publish-mcp.yml\ is created and tested.
• Tagging a release publishes @contextos/mcp\ to the npm registry.
• 
  px @contextos/mcp\ or
  pm i -g @contextos/mcp\ installs and boots the MCP server without runtime errors.