[Feature]: As a lazy user, I would like to be able to input the screenshot of an item, to have the app track it.

### Problem to solve

It makes the process quicker for those who are lazy

### Desired outcome

Take a screenshot of one item on amazon, google, etc. to quickly input what you would like to be tracked

### Proposed solution

_No response_

### Alternatives considered

_No response_

### Additional context

_No response_

### Before submitting

- [x] I searched existing issues and did not find an equivalent request.

No files, tests, or entry points are identified in the issue, so first map the app's existing item-input flow and determine where screenshot input would belong. Done should mean that a screenshot from a supported shopping site can be submitted and the item is added for tracking, with the supported sites and extraction behavior defined.

Written by the indexing model from the issue text.