feat(game): race exit warnings in the turn report (#12)

Surface the inactivity-removal countdown the rules promise but the
engine never reported. A race within five turns of being auto-removed
for inactivity gets a personal warning in its own report; every race
within three turns is listed publicly to all participants.

- model: Report.PersonalExitWarning + RacesLeavingSoon ([]RaceExitNotice)
- fbs: RaceExitNotice table + Report.personal_exit_warning /
  races_leaving_soon (regenerated Go + TS bindings)
- transcoder: encode/decode both fields
- engine: ReportExitWarnings fills the recipient's TTL (1..5) and lists
  other non-extinct races with TTL 1..3, excluding the recipient itself
- ui: danger-styled personal banner + "races leaving soon" section
  (hidden when empty), wired into the report view, EN/RU i18n
- docs: rules.txt report-section list, FUNCTIONAL.md 6.4 + RU mirror

Voluntary quit and idle timeout share the TTL countdown and are not
distinguished, per the agreed scope.

ui/frontend/tests/game-state.test.ts

@@ -29,6 +29,7 @@ import { ByteBuffer } from "flatbuffers";
 import {
 	GameReportRequest,
 	LocalPlanet,
+	RaceExitNotice,
 	Report,
 	ShipClass,
 } from "../src/proto/galaxy/fbs/report";
@@ -124,6 +125,8 @@ function buildReportPayload(opts: {
 	height?: number;
 	planets?: PlanetFixture[];
 	shipClasses?: ShipClassFixture[];
+	personalExitWarning?: number;
+	racesLeavingSoon?: { race: string; turnsLeft: number }[];
 }): Uint8Array {
 	const builder = new Builder(256);
 	const planetOffsets = (opts.planets ?? []).map((planet) => {
@@ -156,6 +159,17 @@ function buildReportPayload(opts: {
 		shipClassOffsets.length === 0
 			? null
 			: Report.createLocalShipClassVector(builder, shipClassOffsets);
+	const racesLeavingSoonOffsets = (opts.racesLeavingSoon ?? []).map((n) => {
+		const race = builder.createString(n.race);
+		RaceExitNotice.startRaceExitNotice(builder);
+		RaceExitNotice.addRace(builder, race);
+		RaceExitNotice.addTurnsLeft(builder, n.turnsLeft);
+		return RaceExitNotice.endRaceExitNotice(builder);
+	});
+	const racesLeavingSoonVec =
+		racesLeavingSoonOffsets.length === 0
+			? null
+			: Report.createRacesLeavingSoonVector(builder, racesLeavingSoonOffsets);
 
 	Report.startReport(builder);
 	Report.addTurn(builder, BigInt(opts.turn));
@@ -168,6 +182,12 @@ function buildReportPayload(opts: {
 	if (localShipClassVec !== null) {
 		Report.addLocalShipClass(builder, localShipClassVec);
 	}
+	if (opts.personalExitWarning !== undefined) {
+		Report.addPersonalExitWarning(builder, opts.personalExitWarning);
+	}
+	if (racesLeavingSoonVec !== null) {
+		Report.addRacesLeavingSoon(builder, racesLeavingSoonVec);
+	}
 	const reportOff = Report.endReport(builder);
 	builder.finish(reportOff);
 	return builder.asUint8Array();
@@ -214,6 +234,52 @@ describe("GameStateStore", () => {
 		store.dispose();
 	});
 
+	test("decodes personalExitWarning and racesLeavingSoon from the report", async () => {
+		listMyGamesSpy.mockResolvedValue([makeGameSummary(7)]);
+
+		const client = makeFakeClient(async () => ({
+			resultCode: "ok",
+			payloadBytes: buildReportPayload({
+				turn: 7,
+				personalExitWarning: 3,
+				racesLeavingSoon: [
+					{ race: "Bajori", turnsLeft: 2 },
+					{ race: "Cardassian", turnsLeft: 1 },
+				],
+			}),
+		}));
+
+		const store = new GameStateStore();
+		await store.init({ client, cache, gameId: GAME_ID });
+
+		expect(store.status).toBe("ready");
+		expect(store.report?.personalExitWarning).toBe(3);
+		expect(store.report?.racesLeavingSoon).toEqual([
+			{ race: "Bajori", turnsLeft: 2 },
+			{ race: "Cardassian", turnsLeft: 1 },
+		]);
+
+		store.dispose();
+	});
+
+	test("defaults personalExitWarning to 0 and racesLeavingSoon to [] when absent", async () => {
+		listMyGamesSpy.mockResolvedValue([makeGameSummary(7)]);
+
+		const client = makeFakeClient(async () => ({
+			resultCode: "ok",
+			payloadBytes: buildReportPayload({ turn: 7 }),
+		}));
+
+		const store = new GameStateStore();
+		await store.init({ client, cache, gameId: GAME_ID });
+
+		expect(store.status).toBe("ready");
+		expect(store.report?.personalExitWarning).toBe(0);
+		expect(store.report?.racesLeavingSoon).toEqual([]);
+
+		store.dispose();
+	});
+
 	test("init surfaces an error when the game is missing from lobby", async () => {
 		listMyGamesSpy.mockResolvedValue([makeGameSummary(0).gameId === "other" ? null : makeGameSummary(0)].filter(Boolean));
 		// Replace the helper above's awkward filter with an explicit