Adds --mode break-glass-drill with its own signed admission (drill:
"break-glass", attempt id RPF-WP-0064-T10-*, snapshot_label). After the
phase A restore and unseal it checks the held root token with lookup-self
only, runs a fresh generate-root ceremony with re-entered shares, does one
read-only sys/auth action, revokes the generated token (204 then 403) and
drills a cancelled attempt. Phase A is unchanged. The verifier types the
receipt extension and rejects token, accessor, OTP, nonce, encoded-token
and share shapes. Offline 34 and native 16 pass. Founder runbooks for the
drill and the read-only production SSO-down walk are in the T10 section.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Assistant: claude-code
Assistant-Model: opus
Assistant-Process: 4515@bnt-lap001
Assistant-Session: 0bf96127-6e04-41be-bfda-d11717c3f354
a2da4085e0