feat: add codebase map context packs

[bntvllnt]

Summary

• add map CLI/operation plus get_codebase_map, get_scope_graph, and get_context_pack MCP surfaces
• produce deterministic graph/context-pack evidence with JSON, Markdown, DOT, and GraphML output
• sync README, docs, llms files, roadmap, registry tests, MCP tests, and real-codebase verification

Review

• $code-review fix loop complete
• Artifact: /tmp/code-review-map-context-pack.json
• Resolved scope graph evidence subset bug in src/mcp/index.ts
• Removed newly introduced TypeScript as assertions in MCP tests

Validation

• pnpm lint
• pnpm typecheck
• pnpm vitest run tests/mcp-tools.test.ts tests/map.e2e.test.ts --reporter=verbose --pool threads --no-file-parallelism --maxWorkers=1
• pnpm test (34 files, 470 tests)
• pnpm verify:cli-real (SUMMARY pass=65 fail=0)
• git diff --check

Release

• Target: 2.5.0 canary train only
• Stable release intentionally not included