refactor(ui): sharpen buttons + inputs to rounded (4px) for modern minimal SaaS look

V2 sharper radii system aligned with Stripe Dashboard / Linear / Vercel
aesthetic — the v1 rounded-lg (8px) on buttons still felt too soft.

New scale:
- Buttons (CTA, submit, ghost, secondary): rounded-lg → rounded (4px)
- Form inputs (text/email/password/select/textarea): rounded-md → rounded (4px)
- Checkboxes: rounded-sm (2px) added explicitly to consent + remember-me
- Cards (pricing, bento, content panels): rounded-xl → rounded-lg (8px)
- Small icon tiles (w-10 h-10 / w-12 h-12 grad-bg squares): rounded-md → rounded
- Pills, badges, avatars, status orbs: rounded-full (KEPT)
- Inline code in legal CSS: rounded (4px) (KEPT)
- Legal blockquote/pre/draft-callout border-radius: 8px → 4px

Files modified (24):
- templates/macros/{button,bento,pricing_card}.html
- templates/marketing/{landing,tarifs,fonctionnalites,conformite,contact}.html
- templates/auth/{check_email,forgot_password,magic_link_request,
  oauth_finish_signup,passkey_setup,reset_password,totp_setup,totp_verify,
  verify_success}.html
- templates/billing/{success,cancel}.html
- templates/legal/{_layout,index}.html
- templates/{register,login}.html
- tests/test_marketing_landing_template.py (assertions updated to match v2)

Verification:
- 18/18 legal page tests pass (tests/_run_legal_pages_windows.py)
- 58/58 marketing landing tests pass

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

templates/marketing/contact.html

@@ -25,8 +25,8 @@
     <div class="grid md:grid-cols-3 gap-6">
 
       {# Email card #}
-      <article class="bg-white p-8 rounded-xl border border-brand-border flex flex-col">
-        <div class="w-12 h-12 grad-bg rounded-md mb-4 flex items-center justify-center text-2xl shadow-cta" aria-hidden="true">✉️</div>
+      <article class="bg-white p-8 rounded-lg border border-brand-border flex flex-col">
+        <div class="w-12 h-12 grad-bg rounded mb-4 flex items-center justify-center text-2xl shadow-cta" aria-hidden="true">✉️</div>
         <h3 class="text-lg font-bold mb-2 text-brand-navy">Courriel</h3>
         <p class="text-sm text-brand-navy/80 mb-4 leading-relaxed flex-grow">
           Privilégiez le courriel pour&nbsp;: pré-inscription, devis, démonstration, dossier de conformité, partenariats.
@@ -35,8 +35,8 @@
       </article>
 
       {# Phone card #}
-      <article class="bg-white p-8 rounded-xl border border-brand-border flex flex-col">
-        <div class="w-12 h-12 grad-bg rounded-md mb-4 flex items-center justify-center text-2xl shadow-cta" aria-hidden="true">☎️</div>
+      <article class="bg-white p-8 rounded-lg border border-brand-border flex flex-col">
+        <div class="w-12 h-12 grad-bg rounded mb-4 flex items-center justify-center text-2xl shadow-cta" aria-hidden="true">☎️</div>
         <h3 class="text-lg font-bold mb-2 text-brand-navy">Téléphone</h3>
         <p class="text-sm text-brand-navy/80 mb-4 leading-relaxed flex-grow">
           Du lundi au vendredi, 9&nbsp;h à 17&nbsp;h (heure de l'Est). Laissez un message en dehors de ces heures.
@@ -45,8 +45,8 @@
       </article>
 
       {# Mailing address card #}
-      <article class="bg-white p-8 rounded-xl border border-brand-border flex flex-col">
-        <div class="w-12 h-12 grad-bg rounded-md mb-4 flex items-center justify-center text-2xl shadow-cta" aria-hidden="true">📬</div>
+      <article class="bg-white p-8 rounded-lg border border-brand-border flex flex-col">
+        <div class="w-12 h-12 grad-bg rounded mb-4 flex items-center justify-center text-2xl shadow-cta" aria-hidden="true">📬</div>
         <h3 class="text-lg font-bold mb-2 text-brand-navy">Bureau</h3>
         <p class="text-sm text-brand-navy/80 mb-4 leading-relaxed flex-grow">
           Sur rendez-vous uniquement. Visites en personne pour démonstrations on-premise et déploiements DictIA 16 corporatifs.
@@ -83,7 +83,7 @@
         {'label': 'Question média / presse', 'subject': 'Question%20m%C3%A9dia', 'icon': '📰'}
       ] %}
       <a href="mailto:info@dictia.ca?subject={{ shortcut.subject }}"
-         class="flex items-center gap-3 bg-brand-bg p-4 rounded-xl border border-brand-border hover:bg-white hover:border-brand-b1/30 transition-colors focus-visible:outline-2 focus-visible:outline-brand-b1 focus-visible:outline-offset-2">
+         class="flex items-center gap-3 bg-brand-bg p-4 rounded-lg border border-brand-border hover:bg-white hover:border-brand-b1/30 transition-colors focus-visible:outline-2 focus-visible:outline-brand-b1 focus-visible:outline-offset-2">
         <span class="text-2xl flex-shrink-0" aria-hidden="true">{{ shortcut.icon }}</span>
         <span class="text-sm font-semibold text-brand-navy">{{ shortcut.label | safe }}</span>
       </a>