fix(marketplace): close client review findings

tests/unit/plugin-marketplace-store.test.ts

@@ -141,6 +141,31 @@ describe('plugin Marketplace store', () => {
     expect(store.getState().installations['makelore.data']).toMatchObject({ status: 'installed' });
   });
 
+  it('merges same-plugin Library and device mutations in either completion order', async () => {
+    for (const order of ['library-then-device', 'device-then-library'] as const) {
+      const acquire = deferred<MarketplaceLibraryProjection>();
+      const install = deferred<MarketplaceInstallation>();
+      const store = createPluginMarketplaceStore({
+        acquire: vi.fn(() => acquire.promise),
+        install: vi.fn(() => install.promise),
+      });
+      store.getState().activateAccount('account-a');
+      const libraryMutation = store.getState().acquire('makelore.notes');
+      const deviceMutation = store.getState().install('makelore.notes');
+      const installed = { status: 'installed' as const, pluginId: 'makelore.notes', version: '1.0.0' };
+      const acquired = { library: library('Notes acquired'), installations: [] };
+      if (order === 'library-then-device') {
+        acquire.resolve(acquired); await libraryMutation;
+        install.resolve(installed); await deviceMutation;
+      } else {
+        install.resolve(installed); await deviceMutation;
+        acquire.resolve(acquired); await libraryMutation;
+      }
+      expect(store.getState().library?.items[0]?.title).toBe('Notes acquired');
+      expect(store.getState().installations['makelore.notes']).toMatchObject(installed);
+    }
+  });
+
   it('calls only the selected state mutation', async () => {
     const acquire = vi.fn().mockResolvedValue(projection('Acquired'));
     const install = vi.fn().mockResolvedValue({ status: 'installed', pluginId: 'makelore.notes', version: '1.0.0' });