feat(frontend): use offline global birth place hierarchy

frontend/tests/birth-place-picker.test.ts

@@ -101,8 +101,8 @@ test("the picker offers three cascading levels instead of a free-text search", (
   assert.match(pickerSource, /aria-label="出生城市"/);
   assert.match(pickerSource, /aria-label="出生区县"/);
   // The level is hidden rather than shown empty when it carries no choice.
-  assert.match(pickerSource, /\{province && !virtualCity && \(/);
-  assert.match(pickerSource, /\{city && districts\.length > 0 && \(/);
+  assert.match(pickerSource, /\{isChina && province && !virtualCity && \(/);
+  assert.match(pickerSource, /\{isChina && city && districts\.length > 0 && \(/);
   assert.match(pickerSource, /不确定，用市区中心/);
   assert.match(pickerSource, /精确到区 \/ 县就足够/);
 });
@@ -126,7 +126,7 @@ test("mounting a saved birth place neither refetches nor clears the stored locat
   // rectified birth-time candidate just because the profile dialog was opened.
   assert.match(pickerSource, /const savedIsCurrent = resolved !== null/);
   assert.match(pickerSource, /if \(syncKey === "saved"\) return;/);
-  assert.match(pickerSource, /if \(saved\.provinceCode \|\| saved\.timezoneId\) onChangeRef\.current\(null\);/);
+  assert.match(pickerSource, /if \(saved\.countryCode !== "CN" \|\| saved\.provinceCode \|\| saved\.timezoneId\) onChangeRef\.current\(null\);/);
   // A changed birth date invalidates the stored offset, so the zone is resolved again.
   assert.match(pickerSource, /mountedMoment === birthMoment/);
 });
@@ -136,7 +136,7 @@ test("the profile stores administrative codes alongside coordinates and the IANA
   assert.match(pageSource, /provinceCode: location\?\.provinceCode \|\| ""/);
   assert.match(pageSource, /cityCode: location\?\.cityCode \|\| ""/);
   assert.match(pageSource, /districtCode: location\?\.districtCode \|\| ""/);
-  assert.match(pageSource, /birthPlaceProvider: location \? "china_locations" : ""/);
+  assert.match(pageSource, /birthPlaceProvider: location\?\.provider \|\| ""/);
   assert.match(pageSource, /timezoneSource: location \? "iana_historical" : ""/);
   assert.match(pageSource, /birth_place_provider_id:\s*nextProfile\.birthPlaceProviderId/);
   assert.match(pageSource, /timezone_id:\s*nextProfile\.timezoneId/);

frontend/tests/world-location-table.test.ts

@@ -0,0 +1,48 @@
+import assert from "node:assert/strict";
+import { existsSync, readFileSync, readdirSync } from "node:fs";
+import { test } from "node:test";
+
+const root = new URL("../", import.meta.url);
+const index = JSON.parse(readFileSync(new URL("src/data/world-countries.json", root), "utf8")) as {
+  source: { repository: string; release: string; license: string };
+  countries: Array<{ code: string; name: string; regionCount: number }>;
+};
+const pickerSource = readFileSync(new URL("src/components/birth-place-picker.tsx", root), "utf8");
+
+test("global location snapshot is country-split and sourced from the pinned release", () => {
+  assert.equal(index.source.repository, "dr5hn/countries-states-cities-database");
+  assert.equal(index.source.release, "v3.2-export.7");
+  assert.equal(index.source.license, "ODbL-1.0");
+  assert.equal(index.countries.length, 229);
+  assert.ok(index.countries.some((country) => country.code === "US"));
+  assert.ok(index.countries.every((country) => country.regionCount > 0));
+
+  const files = new Set(readdirSync(new URL("public/data/world-locations", root)));
+  assert.equal(files.size, index.countries.length);
+  for (const country of index.countries) assert.ok(files.has(`${country.code.toLowerCase()}.json`));
+});
+
+test("country data keeps the coordinates and IANA timezone needed for confirmation", () => {
+  const us = JSON.parse(readFileSync(new URL("public/data/world-locations/us.json", root), "utf8")) as {
+    code: string;
+    regions: Array<{ code: string; cities: Array<{ name: string; latitude: number; longitude: number; timezone: string }> }>;
+  };
+  const california = us.regions.find((region) => region.code === "US-CA");
+  const sanFrancisco = california?.cities.find((city) => city.name === "San Francisco");
+  assert.equal(us.code, "US");
+  assert.ok(california);
+  assert.ok(sanFrancisco);
+  assert.equal(typeof sanFrancisco?.latitude, "number");
+  assert.equal(typeof sanFrancisco?.longitude, "number");
+  assert.equal(sanFrancisco?.timezone, "America/Los_Angeles");
+  assert.equal(existsSync(new URL("src/data/WORLD_LOCATION_DATA.md", root)), true);
+});
+
+test("overseas UI uses cascading data files and has no search input", () => {
+  assert.match(pickerSource, /world-locations\/\$\{draft\.countryCode\.toLowerCase\(\)\}\.json/);
+  assert.match(pickerSource, /海外地点按国家、地区、城市逐级选择，不使用搜索/);
+  assert.match(pickerSource, /aria-label="出生国家或地区"/);
+  assert.match(pickerSource, /aria-label="出生州省或地区"/);
+  assert.match(pickerSource, /aria-label="出生海外城市"/);
+  assert.doesNotMatch(pickerSource, /role="combobox"/);
+});