Closeout package files now actually upload

Attaching an O&M manual, warranty letter, or as-built to a closeout package item used to mark the row ✓ Uploaded without actually storing the file. The checkmark was lying: nothing was saved, and nothing could be opened.

Fixed properly. Uploads now go to your project's document storage, show up in the project's Documents log alongside everything else, and the ✓ is a link that opens the file.

One honest consequence: any closeout file attached before today was never stored, so those rows now read File missing — re-upload instead of a false checkmark. Re-attach the file and you're square. Package status recalculates on real files only.