fix(files): keep reactivity when destructuring the store in grid view

FileEntryGrid destructured useActiveStore() directly, so activeFolder,
activeNode and activeView were plain snapshots taken when the entry was
first rendered. Opening a file from grid view therefore handed the file
actions a stale folder, and the viewer navigated the list to whichever
folder happened to be active back then: from a nested folder this drops
you at the root, or a level or two above, with the file open on top.

Same fix as #59942, which covered FileEntry but left its grid counterpart
behind despite the "keep in sync with FileEntry.vue" note above it.

Signed-off-by: ELHart05 <o.allaoua@esi-sba.dz>

Author: ELHart05

apps/files/src/components/FileEntryGrid.spec.ts

@@ -0,0 +1,69 @@
+/*!
+ * SPDX-FileCopyrightText: 2026 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+import { File, Folder, Permission } from '@nextcloud/files'
+import { createTestingPinia } from '@pinia/testing'
+import { shallowMount } from '@vue/test-utils'
+import { beforeEach, describe, expect, test, vi } from 'vitest'
+import { nextTick } from 'vue'
+import FileEntryGrid from './FileEntryGrid.vue'
+import router from '../router/router.ts'
+import { useActiveStore } from '../store/active.ts'
+
+// useFileListWidth builds its ResizeObserver while the module is evaluated, so
+// the stub has to exist before the import chain runs. jsdom-testing-mocks sets
+// its observer up from a hook, which is already too late here.
+vi.hoisted(() => {
+	globalThis.ResizeObserver = class {
+		observe() {}
+		unobserve() {}
+		disconnect() {}
+	}
+})
+
+vi.mock('@nextcloud/auth')
+
+const source = new File({
+	id: 42,
+	source: 'http://nextcloud.local/remote.php/dav/files/test/Deep/Nested/report.pdf',
+	root: '/files/test',
+	owner: 'test',
+	mime: 'application/pdf',
+	permissions: Permission.READ,
+})
+
+const nestedFolder = new Folder({
+	id: 41,
+	source: 'http://nextcloud.local/remote.php/dav/files/test/Deep/Nested',
+	root: '/files/test',
+	owner: 'test',
+	permissions: Permission.READ,
+})
+
+describe('FileEntryGrid.vue', () => {
+	beforeEach(async () => {
+		await router.replace({ name: 'filelist', params: { view: 'files' } })
+	})
+
+	// The grid entry hands its `activeFolder` to the file actions, so a stale copy
+	// makes opening a file navigate to whichever folder was active when the entry
+	// was first rendered rather than the one the file lives in.
+	test('follows the active folder after navigating', async () => {
+		const wrapper = shallowMount(FileEntryGrid, {
+			propsData: { source, nodes: [source] },
+			mocks: { t: (_: string, text: string) => text },
+			router,
+			pinia: createTestingPinia({ createSpy: vi.fn }),
+		})
+		const activeStore = useActiveStore()
+
+		expect(wrapper.vm.activeFolder).not.toBe(nestedFolder)
+
+		activeStore.activeFolder = nestedFolder
+		await nextTick()
+
+		expect(wrapper.vm.activeFolder).toBe(nestedFolder)
+	})
+})

apps/files/src/components/FileEntryGrid.vue

@@ -71,6 +71,7 @@
 </template>
 
 <script lang="ts">
+import { storeToRefs } from 'pinia'
 import { defineComponent } from 'vue'
 import NcDateTime from '@nextcloud/vue/components/NcDateTime'
 import FileEntryActions from './FileEntry/FileEntryActions.vue'
@@ -117,11 +118,12 @@ export default defineComponent({
 			fileId: currentRouteFileId,
 		} = useRouteParameters()
 
+		const activeStore = useActiveStore()
 		const {
 			activeFolder,
 			activeNode,
 			activeView,
-		} = useActiveStore()
+		} = storeToRefs(activeStore)
 
 		const actions = useFileActions()