[Feature Request]: Implement Support for File Attachments

### Problem Description

Given that AI now supports file attachments, such as gemini-1.0-pro and gemini-1.5-pro-latest (with 1 million tokens currently in private preview access), it would be beneficial to implement this feature.

### Solution Description

> [!NOTE]
> The implementation of this feature should be designed to handle files differently, in order to prevent potential lag caused by storing everything in the browser's local storage.

Also, I am still considering various approaches to improve the method of handling file attachments.

### Alternatives Considered

_No response_

### Additional Context

_No response_