ui/phase-13: planet inspector — read-only

Plumbs the map → inspector pathway: a click on a planet selects it
through the new SelectionStore, the sidebar Inspector tab swaps
its empty-state copy for a per-kind read-only field set, and a
mobile-only bottom-sheet mirrors the same content over the map.
Field projection in api/game-state.ts now surfaces every documented
planet field.

ui/frontend/tests/game-shell-sidebar.test.ts

@@ -1,7 +1,8 @@
 // Component tests for the Phase 10 in-game shell sidebar. Validates
 // the default selected tab, the Calculator / Inspector / Order
-// switching, the empty-state copy that matches the IA section, and
-// the `?sidebar=` URL seed convention used by the mobile bottom-tabs.
+// switching, the empty-state copy that matches the IA section, the
+// `?sidebar=` URL seed convention used by the mobile bottom-tabs,
+// and the Phase 13 selection-driven planet inspector content.
 
 import "@testing-library/jest-dom/vitest";
 import { fireEvent, render } from "@testing-library/svelte";
@@ -14,6 +15,15 @@ import {
 } from "vitest";
 
 import { i18n } from "../src/lib/i18n/index.svelte";
+import {
+	GAME_STATE_CONTEXT_KEY,
+	GameStateStore,
+} from "../src/lib/game-state.svelte";
+import {
+	SELECTION_CONTEXT_KEY,
+	SelectionStore,
+} from "../src/lib/selection.svelte";
+import type { GameReport, ReportPlanet } from "../src/api/game-state";
 
 const pageMock = vi.hoisted(() => ({
 	url: new URL("http://localhost/games/g1/map"),
@@ -26,6 +36,53 @@ vi.mock("$app/state", () => ({
 
 import Sidebar from "../src/lib/sidebar/sidebar.svelte";
 
+function makePlanet(overrides: Partial<ReportPlanet>): ReportPlanet {
+	return {
+		number: 0,
+		name: "",
+		x: 0,
+		y: 0,
+		kind: "local",
+		owner: null,
+		size: null,
+		resources: null,
+		industryStockpile: null,
+		materialsStockpile: null,
+		industry: null,
+		population: null,
+		colonists: null,
+		production: null,
+		freeIndustry: null,
+		...overrides,
+	};
+}
+
+function makeReport(planets: ReportPlanet[]): GameReport {
+	return {
+		turn: 1,
+		mapWidth: 1000,
+		mapHeight: 1000,
+		planetCount: planets.length,
+		planets,
+	};
+}
+
+function withStores(report: GameReport | null): {
+	gameState: GameStateStore;
+	selection: SelectionStore;
+	context: Map<unknown, unknown>;
+} {
+	const gameState = new GameStateStore();
+	gameState.report = report;
+	gameState.status = report === null ? "idle" : "ready";
+	const selection = new SelectionStore();
+	const context = new Map<unknown, unknown>([
+		[GAME_STATE_CONTEXT_KEY, gameState],
+		[SELECTION_CONTEXT_KEY, selection],
+	]);
+	return { gameState, selection, context };
+}
+
 beforeEach(() => {
 	i18n.resetForTests("en");
 	pageMock.url = new URL("http://localhost/games/g1/map");
@@ -95,4 +152,63 @@ describe("game-shell sidebar", () => {
 		await fireEvent.click(ui.getByTestId("sidebar-close"));
 		expect(onClose).toHaveBeenCalledTimes(1);
 	});
+
+	test("inspector tab swaps to the planet view when a planet is selected", async () => {
+		const planet = makePlanet({
+			number: 17,
+			name: "Galactica",
+			kind: "local",
+			x: 50,
+			y: 75,
+			size: 1000,
+			resources: 10,
+			population: 800,
+			colonists: 0,
+			industry: 600,
+			industryStockpile: 0,
+			materialsStockpile: 0,
+			production: "drive",
+			freeIndustry: 200,
+		});
+		const { selection, context } = withStores(makeReport([planet]));
+		const ui = render(
+			Sidebar,
+			{
+				props: { open: false, onClose: () => {} },
+				context,
+			},
+		);
+		expect(ui.getByTestId("sidebar-tool-inspector")).toHaveTextContent(
+			"select an object on the map",
+		);
+
+		selection.selectPlanet(17);
+		await Promise.resolve();
+		expect(ui.queryByText("select an object on the map")).toBeNull();
+		expect(ui.getByTestId("inspector-planet")).toHaveAttribute(
+			"data-planet-id",
+			"17",
+		);
+		expect(ui.getByTestId("inspector-planet-name")).toHaveTextContent(
+			"Galactica",
+		);
+	});
+
+	test("selection that points at a missing planet falls back to the empty state", () => {
+		const { selection, context } = withStores(
+			makeReport([makePlanet({ number: 1, name: "Visible", kind: "local" })]),
+		);
+		selection.selectPlanet(999);
+		const ui = render(
+			Sidebar,
+			{
+				props: { open: false, onClose: () => {} },
+				context,
+			},
+		);
+		expect(ui.queryByTestId("inspector-planet")).toBeNull();
+		expect(ui.getByTestId("sidebar-tool-inspector")).toHaveTextContent(
+			"select an object on the map",
+		);
+	});
 });