feat(bodymap): body map data, endpoint and component

[jalmena]

What

The body map, first half: the shared asset, its endpoint and the component. Lesions and observations follow in the next PR.

• Ported data: MoleMapper's 61 zone identifiers and names and 32 hit polygons, transcribed in tools/bodymap/molemapper_zones.py under the BSD notice in THIRD_PARTY_NOTICES.md (rows now point at the files). The side field is taken from the name, because the identifier digit encodes the screen side, not the patient's.
• Silhouette: neVus artwork, a flat gender-neutral pictogram generated from tapered capsules in tools/bodymap/build.py; both views share it. Polygons are clipped to it, slivers go to the neighbour with the longest shared edge, and the builder asserts an exact tiling with no overlaps. Previews with zone codes in docs/design/bodymap/, notes in docs/design/BODY_MAP.md.
• Asset: zones.json (56 zones, version nevus-body-map/1, normalised coordinates), committed in two identical copies for backend and frontend; CI compares them.
• Backend: nevus.bodymap loader and GET /api/bodymap.
• Frontend: BodyMap (zones as named, focusable buttons; tap yields the zone and the point; markers at normalised positions), ViewToggle, zone names in EN/ES, wired into the person page.
• Tooling: just bodymap; ruff and pre-commit now cover tools/.

Verification

• Backend: ruff, mypy strict, 39 tests (CI also runs PostgreSQL); the JSON is packaged and loads inside the container image.
• Frontend: tsc, eslint + jsx-a11y, stylelint, prettier, 9 component tests, production build.
• OpenAPI snapshot and generated types refreshed.