Auto-attach files based on file paths found in editor text

[badlogic]

When the editor text contains file paths to images (e.g. from pasting a screenshot path), automatically detect and attach them as image attachments.

Example path format:

/var/folders/49/l4171l3n219_xwq30fmyzr8w0000gn/T/TemporaryItems/NSIRD_screencaptureui_k7OmQE/Screenshot 2026-01-12 at 22.52.31.png

This would improve the workflow when users paste screenshot paths into the editor.

Another addition might the introduction of a new prefix ala + which would work like @ except it searches files only and will auto-attach the contents of the file. Needs to consider truncation.