Add confirmation dialog on delete optional attachment

**Jira Ticket**: ALCS-1923

**Description**: There is no confirmation dialog when removing optional attachments in Portal.

Steps:
1. Add optional attachment
2. Click "Remove"

AR: Attachment is removed

ER: A confirmation dialog appears

Apply to Applications, NOIs, and SRWs

**Last Updated**: 2025-02-10 12:09

Start in the Portal attachment removal flows for Applications, NOIs, and SRWs and reproduce the listed steps with an optional attachment. Done means clicking “Remove” opens a confirmation dialog in each flow and the attachment is removed only after confirmation.

Written by the indexing model from the issue text.