refactor(web-panel): update architecture + cheat i18n

Reorganize the panel around product capabilities and integrate the
remote i18n feature from origin/master into the new structure.

- Restructure src into capability features (app, trainer, library,
  remote-session, appearance, shared); move the bridge to bridge/src.
- Add lingui-based UI localization and wrap remaining user-facing
  strings (Trans / msg macros); fix the 'END В·' mojibake.
- Port WeMod cheat-metadata i18n: capture the access token from the
  snapshot's renderer in the bridge and fetch localized trainer_meta
  in remote-session.i18n; guarantee snapshot sync on token failure.
- Wire vitest to the app's lingui/preact pipeline (mergeConfig).

web-panel/src/shared/storage.test.ts

@@ -0,0 +1,19 @@
+import { beforeEach, describe, expect, it } from 'vitest';
+
+import { loadStringSet, saveStringSet } from './storage';
+
+describe('storage revival', () => {
+  beforeEach(() => localStorage.clear());
+
+  it('revives only valid string ids', () => {
+    localStorage.setItem('pins', JSON.stringify(['one', '', 2, 'two']));
+    expect(loadStringSet('pins')).toEqual({ one: true, two: true });
+  });
+
+  it('removes empty sets', () => {
+    saveStringSet('pins', { one: true });
+    expect(localStorage.getItem('pins')).toBe(JSON.stringify(['one']));
+    saveStringSet('pins', {});
+    expect(localStorage.getItem('pins')).toBeNull();
+  });
+});