feat: preserve tabs on sync disconnect/reconnect

Disconnecting a synced list (Google/Outlook/Synology) now uses a
soft-disconnect: tasks are soft-deleted and the external link is
cleared, but the SomedayList record is kept with its tab assignment
intact. When the user reconnects, the import route finds the list by
title, re-links the external provider, and restores tasks (clearing
deletedAt). Tabs survive the full disconnect/reconnect cycle without
the user needing to drag lists back to tabs.

Also clears deletedAt on task re-import so previously disconnected
tasks become visible again on reconnect.

v1.89.0

package.json

@@ -1,6 +1,6 @@
 {
   "name": "my-weekly-todo-list",
-  "version": "1.88.2",
+  "version": "1.89.0",
   "description": "A web-based weekly task management application that organizes to-dos and calendar events in a single, intuitive weekly view",
   "main": "index.js",
   "scripts": {

src/app/api/someday-lists/route.ts

@@ -121,6 +121,8 @@ export async function DELETE(request: NextRequest) {
 
         const { searchParams } = new URL(request.url);
         const id = searchParams.get('id');
+        // tasksOnly=true: soft-disconnect (keep list record with tab, just remove tasks + external link)
+        const tasksOnly = searchParams.get('tasksOnly') === 'true';
 
         if (!id) {
             return NextResponse.json(
@@ -147,6 +149,16 @@ export async function DELETE(request: NextRequest) {
             data: { deletedAt: new Date(), somedayListId: null }
         });
 
+        if (tasksOnly) {
+            // Soft-disconnect: keep list record (preserves tab assignment) but clear external link
+            await prisma.somedayList.update({
+                where: { id },
+                data: { externalId: null, externalProvider: null, lastSyncedAt: null }
+            });
+            notifyUser(userId, "list-changed", { action: "disconnected" });
+            return NextResponse.json({ success: true, kept: true });
+        }
+
         await prisma.somedayList.delete({
             where: { id }
         });

src/app/api/tasks/import/route.ts

@@ -293,7 +293,8 @@ export async function POST(req: NextRequest) {
                         where: { id: existingTask.id },
                         data: {
                             somedayListId: somedayList.id,
-                            lastSyncedAt: new Date()
+                            lastSyncedAt: new Date(),
+                            deletedAt: null,  // clear soft-delete from a previous disconnect
                         }
                     });
                     externalToLocalId.set(task.externalId, existingTask.id);

src/components/WeeklyView.tsx

@@ -3672,10 +3672,13 @@ export default function WeeklyView() {
         );
         if (!existing) { setUnsyncConfirm(null); return; }
         try {
-            const res = await fetch(`/api/someday-lists?id=${existing.id}`, {
+            // tasksOnly=true: soft-disconnect — removes tasks but keeps list record with its tab assignment
+            // so when the user reconnects, the tab is restored automatically without re-dragging
+            const res = await fetch(`/api/someday-lists?id=${existing.id}&tasksOnly=true`, {
                 method: "DELETE",
             });
             if (res.ok) {
+                // Remove from local state (clean UI); DB record is kept for tab restoration on reconnect
                 setSomedayLists((prev) => prev.filter((l) => l.id !== existing.id));
                 setImportStatusMsg({
                     type: "success",
@@ -3683,7 +3686,7 @@ export default function WeeklyView() {
                 });
             }
         } catch (error) {
-            console.error("Failed to delete list", error);
+            console.error("Failed to unsync list", error);
             setImportStatusMsg({
                 type: "error",
                 text: "Failed to stop syncing list.",
@@ -3717,7 +3720,8 @@ export default function WeeklyView() {
                 );
                 if (!existing) continue;
                 try {
-                    const res = await fetch(`/api/someday-lists?id=${existing.id}`, {
+                    // tasksOnly=true: soft-disconnect — keeps list record with tab for reconnect restoration
+                    const res = await fetch(`/api/someday-lists?id=${existing.id}&tasksOnly=true`, {
                         method: "DELETE",
                     });
                     if (res.ok) {