Extract catalog MCP tools

[w1ne]

Summary

• move lookup_cookbook, find_part, and fetch_part registry entries into src/agent/mcp/registry/catalogTools.ts
• move internal MCP registry entry types into src/agent/mcp/registry/types.ts while preserving the public McpToolDefinition export from toolRegistry.ts
• add a public-contract assertion that catalog entries compose back into the same registry slots

Review

• subagent review: no findings; confirmed no docs/fixtures changed, no catalog module import cycle, public fixture coverage intact

Verification

• red: focused public contract test failed before implementation because ./registry/catalogTools did not exist
• npm test -- src/agent/mcp/toolRegistry.publicContract.test.ts
• npm test -- src/agent/mcp/toolRegistry.publicContract.test.ts src/agent/mcp/toolNameConsistency.test.ts tests/integration/mcp/serverToolDispatch.test.ts tests/unit/mcp/toolRegistrySchema.test.ts tests/unit/scripts/distToolNameGate.test.ts tests/unit/skill/skillToolCountDrift.test.ts tests/integration/mcp/listApi.driftSentinel.test.ts
• npm run typecheck