fix: scope qtmaildir: allow to the exact document base URL

Whole-scheme allow meant a hostile message body could reference any
qtmaildir: URL (e.g. <img src="qtmaildir://other">) and have it pass,
with safety depending entirely on Task 11's still-unwritten scheme
handler. Add setDocumentUrl() and require an exact QUrl match; deny
all qtmaildir: URLs when it is unset (fail closed). Document URL
survives resetForNewMessage() since it is a property of the view, not
of a message.

0 files changed, 0 insertions, 0 deletions