Re-verify the 28 hi-fi screens against the current design deck

[antosubash]

Split out of #301, whose other half (the Keycloak interstitial and its screenshots) closed in #316.

Every screen in docs/superpowers/specs/2026-09-03-hifi-pages-design.md was matched against an export of Hi-Fi Pages.dc.html (project 4ad8fe06-c68f-4444-bcf7-0d0b4839e681) taken on 2026-08-19, because the live design file could not be read while the work was in progress. Any edit made to the deck after that date is reflected neither in the implementation nor in the spec's Deliberate departures table.

This needs someone with access to the design file. It is not in the repo, and two separate passes have now hit the same wall:

• fix(ui): give the shared components the behaviour their roles promise #313 (packages/ui accessibility and deck fidelity) sized the auth controls from docs/superpowers/specs/hifi-gap/auth-screens-02-07.md — the repo's own gap-analysis notes — rather than from the deck, and said so.
• fix(keycloak): capture the interstitial that screen 07's evidence never showed #316 could not check screen 07's layout against the deck either.

What "done" looks like

• One pass over all 28 screens against the current file.
• Any post-2026-08-19 deck change either implemented, or added to Deliberate departures with a reason.
• The spec's cached-export caveat removed once the deck is genuinely satisfied.

Screenshots for comparison are in qa-shots/hifi/. Note screen 07's pair can only be regenerated with scripts/shoot_keycloak_interstitial.py against a server booted with SM_AUTH_PROVIDER=keycloak — see that script's docstring.