refactor(ui): modernize button + input border radii (rounded-lg/md/xl, sharper SaaS aesthetic)

Aligns DictIA marketing/auth/legal/billing templates with modern SaaS visual
conventions (Linear, Vercel, Stripe Dashboard, Notion). Old radii (12-18px)
felt dated; new system uses 6-12px for tighter, more contemporary corners.

Border radius system:
- Buttons (CTA, submit, secondary): rounded-[0.75rem] (12px) -> rounded-lg (8px)
- Form inputs (text/email/password/select/textarea/checkbox): rounded-[0.5rem] -> rounded-md (6px)
- Cards (pricing, bento, modals, content panels): rounded-[18px]/[14px]/[12px] -> rounded-xl (12px)
- Pricing card outer gradient frame: rounded-[20px] -> rounded-xl (matches inner)
- Pills / badges / status chips: KEEP rounded-full
- Avatars / circular icon containers: KEEP rounded-full
- Code blocks: KEEP rounded (4px)

Decision tree applied for ambiguous cases:
- Button-like clickable CTA -> rounded-lg
- Form input -> rounded-md
- Card / panel / modal -> rounded-xl
- Badge / pill / chip / avatar -> rounded-full (preserved)

In-scope templates modified (23):
- macros/button.html (central macro, cascades to all callers)
- macros/pricing_card.html, macros/bento.html
- marketing/landing.html, tarifs.html, fonctionnalites.html, conformite.html, contact.html
- auth/check_email.html, forgot_password.html, magic_link_request.html, oauth_finish_signup.html,
  passkey_setup.html, reset_password.html, totp_setup.html, totp_verify.html, verify_success.html
- billing/cancel.html, billing/success.html
- legal/_layout.html, legal/index.html
- register.html, login.html

Out of scope (untouched): index.html, account.html, admin.html, share.html, inquire.html,
group-admin.html, components/**, includes/**, modals/** (all legacy Speakr Vue surfaces).

Tests: test_marketing_landing_template.py — 2 assertions updated to match new bento icon
(rounded-md) and pricing card frame (rounded-xl). All 18 legal tests + 58 marketing landing
tests + 9 signup_loi25 tests still pass. Decorative rounded-full preserved on hero cosmic
orbs and ordres-pros avatar circles.

Diff: 94 insertions / 94 deletions (1:1 mechanical replacement, no class drift).

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-[18px] border border-brand-border flex flex-col">
-        <div class="w-12 h-12 grad-bg rounded-[0.5rem] mb-4 flex items-center justify-center text-2xl shadow-cta" aria-hidden="true">✉️</div>
+      <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>
         <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-[18px] border border-brand-border flex flex-col">
-        <div class="w-12 h-12 grad-bg rounded-[0.5rem] mb-4 flex items-center justify-center text-2xl shadow-cta" aria-hidden="true">☎️</div>
+      <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>
         <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-[18px] border border-brand-border flex flex-col">
-        <div class="w-12 h-12 grad-bg rounded-[0.5rem] mb-4 flex items-center justify-center text-2xl shadow-cta" aria-hidden="true">📬</div>
+      <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>
         <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-[14px] 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-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">
         <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>