test(desktop): restore web storage under Node 22+

Node 22+ defines a global `localStorage` accessor that stays inert
unless the process was started with `--localstorage-file`. vitest's
jsdom environment only copies a window key onto `globalThis` when
nothing is there yet, so Node's inert stub wins over jsdom's real
Storage and `window.localStorage` reads back undefined.

Every suite whose `beforeEach` calls `localStorage.clear()` therefore
died at setup, taking the whole file with it — 12 files and 396 tests
on a clean tree, none of them a real failure. Install a Storage
implementation from a setup file so browser semantics hold regardless
of Node version.

Local desktop suite: 396 failures across 12 files -> 2 across 1.

desktop/src/test/webStorage.ts

@@ -0,0 +1,57 @@
+/**
+ * Node 22+ defines a global `localStorage` / `sessionStorage` accessor that
+ * stays inert unless the process was started with `--localstorage-file`.
+ * vitest's jsdom environment only copies a window key onto `globalThis` when
+ * nothing is there yet, so Node's inert stub wins over jsdom's real Storage and
+ * every `localStorage.clear()` in a `beforeEach` throws. Installing a real
+ * Storage here restores browser semantics regardless of Node version.
+ */
+class MemoryStorage implements Storage {
+  #entries = new Map<string, string>()
+
+  get length(): number {
+    return this.#entries.size
+  }
+
+  key(index: number): string | null {
+    return [...this.#entries.keys()][index] ?? null
+  }
+
+  getItem(key: string): string | null {
+    return this.#entries.get(String(key)) ?? null
+  }
+
+  setItem(key: string, value: string): void {
+    this.#entries.set(String(key), String(value))
+  }
+
+  removeItem(key: string): void {
+    this.#entries.delete(String(key))
+  }
+
+  clear(): void {
+    this.#entries.clear()
+  }
+
+  [name: string]: unknown
+}
+
+function installStorage(name: 'localStorage' | 'sessionStorage'): void {
+  let usable = false
+  try {
+    const existing = (globalThis as Record<string, unknown>)[name] as Storage | undefined
+    usable = typeof existing?.setItem === 'function' && typeof existing?.clear === 'function'
+  } catch {
+    // Node's accessor throws when web storage is unavailable — treat as missing.
+  }
+  if (usable) return
+
+  Object.defineProperty(globalThis, name, {
+    value: new MemoryStorage(),
+    configurable: true,
+    writable: true,
+  })
+}
+
+installStorage('localStorage')
+installStorage('sessionStorage')

desktop/vitest.config.ts

@@ -13,7 +13,7 @@ export default defineConfig({
     environment: 'jsdom',
     globals: true,
     css: true,
-    setupFiles: [],
+    setupFiles: ['./src/test/webStorage.ts'],
     coverage: {
       include: ['src/**/*.{ts,tsx}'],
       exclude: [
@@ -21,6 +21,7 @@ export default defineConfig({
         'src/**/*.d.ts',
         'src/types/**',
         'src/mocks/**',
+        'src/test/**',
         'src/vite-env.d.ts',
       ],
     },