MCP adapter v1: read-only MAP architecture tools

[rajanbor]

Outcome

Expose stable MAP application ports to MCP clients without moving protocol concerns into the core.

Initial tools

• list/search/show patterns
• inspect graph
• scan project
• suggest patterns
• validate MAP workspace

Constraints

• separate package and dependency boundary
• read-only first release
• approved workspace roots and bounded paths
• same result contracts and semantics as CLI
• no alternate pattern model or hidden LLM dependency

Acceptance criteria

• Threat model documents path, prompt-content, and denial-of-service risks
• Contract tests compare MCP and CLI results for the same fixtures
• Tool descriptions state evidence limits and non-mutation guarantees
• Core builds and tests without MCP dependencies
• Write tools remain out of scope pending a separate ADR

Depends on #103 and follows ADR-0006.