feat(ui): make stat numbers clickable to open games

StatDrill context holds one dialog for a page. StatCount wraps a number:
total and status counts link to the library filter, other numbers open
StatGamesDialog. DrillRow and DrillButton support drill-down in tag bars
(genres, platforms, moods) and other stat displays. Dialog shows 40 games
per page with bottom-sheet layout on phones, handles pagination and errors
(403 not shared, 401 expired, 400 bad argument).

src/utils/statGames.js

@@ -0,0 +1,54 @@
+import {request} from './api.js';
+
+const CORE = () => import.meta.env.VITE_CORE_API_URL;
+
+const query = (params) => params
+    .filter(([, value]) => value != null && value !== '')
+    .map(([name, value]) => `${name}=${encodeURIComponent(value)}`)
+    .join('&');
+
+/**
+ * The URL of one page of the games behind a number.
+ *
+ * @param source own, profile, community or points
+ * @param track points: the unlock track of a locked bar
+ * @param kind points: the history kind (MONTH or STREAK) with its `ref`
+ */
+export function statGamesUrl({source, key, arg, page = 0, track, kind, ref}) {
+    const base = `${CORE()}/api`;
+    if (source === 'points') {
+        const path = track
+            ? `progress/${encodeURIComponent(track)}`
+            : `history/${encodeURIComponent(kind)}/${encodeURIComponent(ref)}`;
+        return `${base}/rewards/${path}/games?${query([['page', page]])}`;
+    }
+    const path = {
+        own: 'library/stats/games',
+        profile: 'public/profiles/library/stats/games',
+        community: 'stats/public/games',
+    }[source];
+    return `${base}/${path}?${query([['key', key], ['arg', arg], ['page', page]])}`;
+}
+
+/**
+ * `{ok, status, data}` like `request`. The profile and the community list are public: no login, no refresh.
+ */
+export async function fetchStatGames(source, params, ticket) {
+    const url = statGamesUrl({source, ...params});
+    if (source !== 'profile' && source !== 'community') return request(url);
+    try {
+        const response = await fetch(url, source === 'profile' ? {headers: {'X-Profile-Ticket': ticket}} : undefined);
+        return {ok: response.ok, status: response.status, data: response.ok ? await response.json() : null};
+    } catch (err) {
+        console.error(`Request to ${url} failed:`, err);
+        return {ok: false, status: 0, data: null};
+    }
+}
+
+export const libraryLink = (status) => `/library?hideDuplicates=true${status ? `&status=${status}` : ''}`;
+
+// A visitor has no game page of the owner; the Steam store is the only public one. Manual games have no appid there.
+export const gameHref = (appid, own) => {
+    if (own) return `/library/${appid}`;
+    return appid > 0 ? `https://store.steampowered.com/app/${appid}` : null;
+};

src/utils/statGames.test.js

@@ -0,0 +1,35 @@
+import {describe, expect, it} from 'vitest';
+import {gameHref, libraryLink, statGamesUrl} from './statGames.js';
+
+describe('statGamesUrl', () => {
+    it('own_EncodesTheArgAndPage', () => {
+        expect(statGamesUrl({source: 'own', key: 'GENRE', arg: 'Role-Playing & Co', page: 2}))
+            .toMatch(/\/api\/library\/stats\/games\?key=GENRE&arg=Role-Playing%20%26%20Co&page=2$/);
+    });
+
+    it('profile_And_Community_UseTheirPaths', () => {
+        expect(statGamesUrl({source: 'profile', key: 'PILE'})).toMatch(/\/api\/public\/profiles\/library\/stats\/games\?key=PILE&page=0$/);
+        expect(statGamesUrl({source: 'community', key: 'OWNED'})).toMatch(/\/api\/stats\/public\/games\?key=OWNED&page=0$/);
+    });
+
+    it('points_TrackAndHistory', () => {
+        expect(statGamesUrl({source: 'points', track: 'GAMES_FINISHED'})).toMatch(/\/api\/rewards\/progress\/GAMES_FINISHED\/games\?page=0$/);
+        expect(statGamesUrl({source: 'points', kind: 'MONTH', ref: '2026-09', page: 1}))
+            .toMatch(/\/api\/rewards\/history\/MONTH\/2026-09\/games\?page=1$/);
+    });
+});
+
+describe('libraryLink', () => {
+    it('addsTheStatusOnlyWhenGiven', () => {
+        expect(libraryLink()).toBe('/library?hideDuplicates=true');
+        expect(libraryLink('BACKLOG')).toBe('/library?hideDuplicates=true&status=BACKLOG');
+    });
+});
+
+describe('gameHref', () => {
+    it('own_LinksTheLibraryPage', () => expect(gameHref(5, true)).toBe('/library/5'));
+    it('visitor_LinksTheStoreOnlyForSteamApps', () => {
+        expect(gameHref(5, false)).toBe('https://store.steampowered.com/app/5');
+        expect(gameHref(-3, false)).toBeNull();
+    });
+});