[CH] simdjson doesn't support strings which contain invalid unicodes

### Backend

CH (ClickHouse)

### Bug description

[Expected behavior] and [actual behavior].

simdjson fails to parse following json
```
{"a":"431924697b1\ufffdSC\u2995\u06a2\r8\u0010\u06e3\udee4\udff0L\u0001Y"}
```
`\udee4` and `\udff0` are invalid unicodes

### Spark version

None

### Spark configurations

_No response_

### System information

_No response_

### Relevant logs

_No response_

Start by reproducing the reported JSON through the ClickHouse simdjson path, focusing on the invalid surrogate sequences \udee4 and \udff0. Clarify the expected and actual behavior, then verify that the same input is handled correctly without breaking valid JSON parsing.

Written by the indexing model from the issue text.