Make the default button press subtle; small controls keep the stronger one

Default :active scale is now 0.99. .btn-icon, .btn-sm and data-press=small keep
0.96; full-screen backdrops opt out with data-press=none. Renew design-contract
hashes for the touched dynamic owners.

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>