Missing payload attachments fix

[ryangalea7]

Problem

Laravel does not include file attachments in $request->input(), which caused the webhook client to miss uploaded files when building the payload. As a result, attachments were silently dropped and could not be accessed later.

Solution

This PR explicitly extracts uploaded files from $request->allFiles(), encodes their content, and appends them to the payload. The getAttachments() method then reconstructs these files into UploadedFile instances using temporary files.

Changes

• Files are extracted, base64-encoded, and added under the attachments key in the payload.
• New getAttachments() method reads from the payload and rebuilds the files.

Notes

• The attachment data is tested and works alongside the other regular payload information.
• This has not been tested for backwards compatibility, so do consider testing this if it's a requirement.