text trigger attach file not working

###Bug: File Protocol Fetch Blocked in Browsers

The `FileControlModule`'s `handleFileAttach` method attempts to read local files using `fetch('file://...')`. This fails in browser environments due to security policies that block `fetch` requests to the `file://` protocol, resulting in a network error and preventing file attachment.

src/controls/modules/FileControlModule.ts#L164-L204

https://github.com/DimitriGilbert/LiteChat/blob/319d2d771bf78ec2e46002028042214e2ed1a8ac/src/controls/modules/FileControlModule.ts#L164-L204