add world opinions project

World map with switchable layers (what "liberal" means, what left vs right
is about, traditional/secular and survival/self-expression values), country
cards, a shared-scale party compass, a values scatter and national
narratives of major events.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/lib/world-opinions/data.test.ts

@@ -0,0 +1,44 @@
+import { describe, expect, it } from 'vitest';
+import world from 'world-atlas/countries-110m.json';
+import { countries, countryById, narratives, parties, partyCountries, profiles } from './data';
+
+describe('world opinions data', () => {
+	it('has unique country ids and ISO codes', () => {
+		expect(new Set(countries.map((country) => country.id)).size).toBe(countries.length);
+		expect(new Set(countries.map((country) => country.iso)).size).toBe(countries.length);
+	});
+
+	it('matches every country to a shape on the map', () => {
+		const shapes = new Set(
+			world.objects.countries.geometries.map((shape: { id?: string }) => String(shape.id))
+		);
+		for (const country of countries) expect(shapes.has(country.iso), country.name).toBe(true);
+	});
+
+	it('only references known countries', () => {
+		const referenced = [
+			...profiles.map((profile) => profile.id),
+			...partyCountries,
+			...parties.map((party) => party.country),
+			...narratives.flatMap((narrative) => narrative.views.map((view) => view.country))
+		];
+		for (const id of referenced) expect(countryById.has(id), id).toBe(true);
+	});
+
+	it('keeps party positions on the 0–10 scale with unique keys', () => {
+		const keys = new Set(parties.map((party) => `${party.country}-${party.short}`));
+		expect(keys.size).toBe(parties.length);
+		for (const party of parties) {
+			for (const value of [party.econ, party.social]) {
+				expect(value).toBeGreaterThanOrEqual(0);
+				expect(value).toBeLessThanOrEqual(10);
+			}
+		}
+		for (const id of partyCountries) {
+			expect(
+				parties.some((party) => party.country === id),
+				id
+			).toBe(true);
+		}
+	});
+});