feat: add JD mother living time endpoint

server-tools/tcs-mother-body/living-time.test.mjs

@@ -0,0 +1,17 @@
+import assert from "node:assert/strict";
+import test from "node:test";
+import { livingTime } from "./living-time.mjs";
+
+test("birth boundary is era day one", () => {
+  const value = livingTime(Date.parse("2025-04-25T16:00:00.000Z"));
+  assert.equal(value.world.era_day, 1);
+  assert.equal(value.world.elapsed_milliseconds, 0);
+});
+
+test("milliseconds advance without wake counter", () => {
+  const first = livingTime(Date.parse("2026-09-09T00:00:00.000Z"));
+  const second = livingTime(Date.parse("2026-09-09T00:00:00.017Z"));
+  assert.equal(second.world.elapsed_milliseconds - first.world.elapsed_milliseconds, 17);
+  assert.equal(second.clock.stored_tick_counter, false);
+  assert.equal(second.clock.persona_wake_required, false);
+});