test(core): use in-memory DB for logEntry truncation test

The logEntry()-bounds test does 1005 sequential SQLite writes and was
timing out at 20s on a disk-backed TaskStore. It doesn't exercise
cross-instance persistence, so flip on inMemoryDb to bring it under 8s.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

packages/core/src/__tests__/store.test.ts

@@ -9818,7 +9818,7 @@ describe("RunMutationContext", () => {
     const localRoot = makeTmpDir();
     const localGlobal = makeTmpDir();
     try {
-      const localStore = new TaskStore(localRoot, localGlobal);
+      const localStore = new TaskStore(localRoot, localGlobal, { inMemoryDb: true });
       await localStore.init();
 
       const task = await localStore.createTask({ description: "Test task" });