@ cantoo/pdf-lib 2.9.1 was already the dep in use; the encryption plumbing
and probe were already in place from the prior hardening pass. This commit:
- adds a test confirming executeOperation('permissions', ...) routes through
pdfSetPermissions and produces an encrypted PDF unlocked by the owner
password (mirrors the existing 'encrypt' route coverage)
- updates docs/superpowers/plans/2026-08-23-security-assessment-summary.md
to mark deferred risk D1 as resolved (the honest-failure message remains
as a fail-closed net for any future library regression)
35 PDF ops tests pass; lint/format clean.
Amit Haridas
Final-review nit: the hardcoded-list rationale covers the dialog path
only; the drop stands on the trusted-argv precedent for --convert-to.
Amit Haridas