The single node ns and tablet are stopped and then started, and the data cannot be recovered

**Bug Description**
The single node ns and tablet are stopped and then started, and the data cannot be recovered

**Expected Behavior**
Data can be recovered

**Steps to Reproduce**

1. tablet stop
2. ns stop
3. ns start
4. tablet start
5. showopstatus
6. showtable

The issue describes a data recovery failure after restarting ns (nameserver) and tablet components in a single-node setup. Start by examining the startup and recovery logic in the nameserver and tablet code, likely in src/nameserver and src/tablet directories. Look for logs or tests related to 'showopstatus' and 'showtable' commands to understand the expected state. Reproduce the steps locally to see the failure, then trace through the recovery flow to identify where data persistence or replication is broken.

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