interval is truncated to wrong value

## Bug Report

Please answer these questions before submitting your issue. Thanks!

### 1. Minimal reproduce step (Required)

```
SELECT SUBDATE(_utf8mb4'2024-01-01', INTERVAL X'01' DAY)
```

### 2. What did you expect to see? (Required)

```
mysql> SELECT SUBDATE(_utf8mb4'2024-01-01', INTERVAL X'01' DAY);
+---------------------------------------------------+
| SUBDATE(_utf8mb4'2024-01-01', INTERVAL X'01' DAY) |
+---------------------------------------------------+
| 2023-12-31 |
+---------------------------------------------------+
1 row in set (0.00 sec)
```

### 3. What did you see instead (Required)

```
mysql> SELECT SUBDATE(_utf8mb4'2024-01-01', INTERVAL X'01' DAY);
+---------------------------------------------------+
| SUBDATE(_utf8mb4'2024-01-01', INTERVAL X'01' DAY) |
+---------------------------------------------------+
| 2024-01-01 |
+---------------------------------------------------+
1 row in set, 1 warning (0.01 sec)
```

### 4. What is your TiDB version? (Required)

Start by running the reported SUBDATE query in TiDB and compare its result and warning with the expected MySQL-style result. Trace the SQL date-interval handling until the X'01' DAY value is converted, then verify that the query returns 2023-12-31 without the incorrect truncation warning.

Written by the indexing model from the issue text.