Color picker on the 'mask editor' is not exact (video)

### Prerequisites

- [x] I am running the latest version of ComfyUI
- [x] I have custom nodes enabled

### What happened?

The vid show it all. The color picker does not pick the exact color .

Vid:
https://youtu.be/K35U_oOqSfo

Same vid, but as low-res gif:

### Steps to Reproduce

1. upload image
2. mask editor
3. color tab
4. use color picker
6. The color picker did not select the exact color

### Workflow

N/A

### How is this affecting you?

Minor inconvenience

### ComfyUI Frontend Version

1.49.8

### Browser

Edge

### Console Errors

```javascript

```

### Logs

```shell

```

### Additional Context

_No response_

Start by reproducing the issue in ComfyUI Frontend 1.49.8: upload an image, open the mask editor, select the color tab, and use the picker while comparing it with the provided video and screenshots. Trace the mask editor's color-picker entry point and verify that the selected value matches the exact sampled image color when the fix is complete.

Written by the indexing model from the issue text.