fix(tests): chat thread-settings test is idempotent

The row the test writes survives the backup/restore cycle (plugin
tables aren't in the export), so on the second run the GET returned
1 and the "starts at 0" assertion blew up. Explicitly reset the
flag at the start, then flip, then reset again — each run lands
the DB in the same state it started.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

public/plugins/tests/chat.test.js

@@ -120,18 +120,22 @@ describe('Chat: API', () => {
 
     it('/api/chat/thread-settings round-trips disposable flag', async () => {
         const peer = '__test_disposable_flip__';
-        const initial = await fetch('api/chat/thread-settings?peer=' + encodeURIComponent(peer))
-            .then(r => r.json());
-        expect(initial.disposable).toBe(0);
-        const set = await fetch('api/chat/thread-settings', {
+        const setFlag = (v) => fetch('api/chat/thread-settings', {
             method: 'POST',
             headers: { 'Content-Type': 'application/json', 'X-CSRF-Token': csrf() },
-            body: JSON.stringify({ peer, disposable: true }),
+            body: JSON.stringify({ peer, disposable: v }),
         }).then(r => r.json());
+        // Reset from any leftover state (previous runs leave the row
+        // behind — restore only rolls cards/buckets, not plugin tables).
+        const reset = await setFlag(false);
+        expect(reset.disposable).toBe(0);
+        const set = await setFlag(true);
         expect(set.disposable).toBe(1);
         const after = await fetch('api/chat/thread-settings?peer=' + encodeURIComponent(peer))
             .then(r => r.json());
         expect(after.disposable).toBe(1);
+        // Leave a clean slate for the next run.
+        await setFlag(false);
     });
 });