# Implementation Plan

1. Add area output/config normalization and command entrypoints for the native
   compiler, preserving existing stage behavior and paths.
2. Implement a shared OSM road parser and canonical road/endpoints model with
   source provenance, explicit versus inferred properties, and stable IDs.
3. Implement v1 override schema, validation, load/apply behavior, atomic save,
   and focused unit tests.
4. Implement projected road segment geometry, supported T/cross junction
   detection, native GeoJSON artifact emission, diagnostics, and comparison
   summary.
5. Implement a dependency-free local workbench server and browser UI with
   selection, provenance display, v1 parameter/topology editing, explicit save,
   compile/reload, and error states.
6. Add native compiler tests using focused fixtures plus nantaizi analysis;
   run existing relevant Node tests to confirm legacy behavior remains intact.
7. Compare nantaizi and at least one supplied problematic OSM sample. Record
   metrics, unsupported cases, and follow-up work in task research.

## Validation

```bash
npm run road:compile -- --config config/areas/nantaizi-lake-innovation-valley.json
npm run road:workbench -- --config config/areas/nantaizi-lake-innovation-valley.json
npm run test:build-stages
npm run test:preflight
npm run test:preview-assets
```

Browser validation includes loading the workbench, editing a road parameter,
saving, verifying the override file, recompiling, reloading, and confirming
provenance identifies the saved override.