feat: reminder button in list/tabs view, notifications show reminders, trash count live update

- Add reminder action to NoteActions (masonry view) and NoteMetaSidebar (tabs view)
- NotificationPanel now fetches and displays upcoming/overdue reminders alongside share requests
- Badge count includes overdue reminders; overdue items show mark-as-done toggle
- Sidebar trash count refreshes on NoteRefreshContext trigger (no more manual refresh)
- Add "Clear completed" button on reminders page with clearCompletedReminders action
- Add i18n keys for new features (en/fr)

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

memento-note/app/actions/notes.ts

@@ -319,6 +319,31 @@ export async function toggleReminderDone(noteId: string, done: boolean) {
   }
 }
 
+// Clear completed reminders (set reminder to null for done reminders)
+export async function clearCompletedReminders() {
+  const session = await auth();
+  if (!session?.user?.id) return { error: 'Unauthorized' }
+
+  try {
+    await prisma.note.updateMany({
+      where: {
+        userId: session.user.id,
+        isReminderDone: true,
+        reminder: { not: null },
+      },
+      data: {
+        reminder: null,
+        isReminderDone: false,
+      },
+    })
+    revalidatePath('/reminders')
+    return { success: true }
+  } catch (error) {
+    console.error('Error clearing completed reminders:', error)
+    return { error: 'Failed to clear reminders' }
+  }
+}
+
 // Get archived notes only
 export async function getArchivedNotes() {
   const session = await auth();