Incorrect formatting for numerical values in Form answers imported to Sheet

### Description

From a support ticket: when numerical Form answers are imported into Sheet, they cannot be summed with a formula, as they are an incorrect format (and cannot be reformatted using highlight>right click>format cells)

### Steps to reproduce

1. Make a Form with a (required) question type 'Text' and Text type 'Number'.
2. Answer the Form several times so you have several numbers.
3. Go to the Responses and click on the button 'Export to Sheet'
4. Add a formula to sum the cells with the numbers.
5. The result of the sum is zero.
6. When selecting the cells with the numbers, the status bar only shows the count.

### Relevant logs

```shell

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### Expected behavior

- The result of the sum is the count of the numbers in summed cells.
- When selecting the cells with the numbers, the status bar shows the average, count, min, max and sum.

### Which operating system are you using?

_No response_

### What browsers are you seeing the problem on?

_No response_

### Extensions

n/a

### Version

2026.2.0