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/landing.html

@@ -140,7 +140,7 @@
         ('Loi 25 — biométrie', 'Sanctions CAI jusqu\'à 25 M$', 'La voix est une donnée biométrique au sens des articles 44-45 de la LCCJTI et un renseignement sensible au sens de la Loi 25 (art. 12 LSP). Tout traitement nécessite un consentement explicite, une déclaration préalable à la CAI et un transfert vers un territoire offrant une protection équivalente — ce que les États-Unis n\'offrent pas.', '🛡️'),
         ('Sanctions disciplinaires', '~250 000 pros réglementés QC (CIQ)', 'Les ordres professionnels québécois — au premier rang desquels le Barreau, la Chambre des notaires et CPA Québec — exigent une obligation stricte de confidentialité. Le transfert de données client hors-juridiction sans consentement explicite peut être qualifié de manquement, jusqu\'à la radiation pour les fautes graves.', '⚠️')
       ] %}
-      <article class="bg-white p-6 rounded-[0.75rem] border border-brand-border">
+      <article class="bg-white p-6 rounded-lg border border-brand-border">
         <div class="text-3xl mb-4" aria-hidden="true">{{ card[3] }}</div>
         <h3 class="text-lg font-bold mb-1 text-brand-navy">{{ card[0] }}</h3>
         <p class="text-xs uppercase tracking-wider text-brand-navy/70 mb-3 font-semibold">{{ card[1] | safe }}</p>
@@ -175,8 +175,8 @@
         ('Conforme Loi&nbsp;25', 'Audit trail intégré (qui a écouté quoi, quand). Déclaration CAI prête. Consentement explicite tracé pour chaque enregistrement. Code source AGPL v3 — transparence vérifiable.'),
         ('Précision FR-CA', 'WhisperX Large-v3 fine-tuné français québécois. Diarisation pyannote 8 locuteurs. Résumés Mistral 7B local — aucune connexion OpenAI/Google/Microsoft.')
       ] %}
-      <article class="bg-white/[0.05] backdrop-blur-sm p-6 rounded-[0.75rem] border border-white/[0.08]">
-        <div class="w-10 h-10 grad-bg rounded-[0.5rem] mb-4 flex items-center justify-center font-black text-white shadow-cta" aria-hidden="true">✓</div>
+      <article class="bg-white/[0.05] backdrop-blur-sm p-6 rounded-lg border border-white/[0.08]">
+        <div class="w-10 h-10 grad-bg rounded-md mb-4 flex items-center justify-center font-black text-white shadow-cta" aria-hidden="true">✓</div>
         <h3 class="text-lg font-bold mb-2 text-white">{{ pillar[0] | safe }}</h3>
         <p class="text-sm text-white/70 leading-relaxed">{{ pillar[1] | safe }}</p>
       </article>
@@ -198,7 +198,7 @@
     {# NOTE: bento card content is duplicated between landing.html and fonctionnalites.html.
        When editing, sync both files. Future refactor: extract to _partials/_bento_features.html. #}
     {% from 'macros/bento.html' import bento_card %}
-    <div class="grid grid-cols-1 sm:grid-cols-2 md:grid-cols-3 gap-[1.5px] bg-brand-border rounded-[18px] overflow-hidden">
+    <div class="grid grid-cols-1 sm:grid-cols-2 md:grid-cols-3 gap-[1.5px] bg-brand-border rounded-xl overflow-hidden">
       {{ bento_card('01', 'Transcription WhisperX', 'Large-v3 fine-tuné FR-CA. Précision 95&nbsp;%+ sur réunions, dictées, audiences (méthodologie disponible sur demande).', '🎙️') }}
       {{ bento_card('02', 'Diarisation 8 locuteurs', 'pyannote sépare automatiquement les intervenants. Identification par embeddings vocaux.', '👥') }}
       {{ bento_card('03', 'Résumés Mistral 7B', 'IA locale génère résumés, points d\'action et procès-verbaux. Aucune connexion cloud.', '📝') }}
@@ -225,7 +225,7 @@
     {% include 'marketing/_partials/_pricing_tiers.html' %}
 
     {# ROI CALCULATOR — Alpine.js, hypotheses transparentes pour LPC art. 219 hygiene #}
-    <div x-data="roiCalculator()" class="mt-16 max-w-3xl mx-auto bg-white p-8 rounded-[18px] border border-brand-border" aria-labelledby="roi-title">
+    <div x-data="roiCalculator()" class="mt-16 max-w-3xl mx-auto bg-white p-8 rounded-xl border border-brand-border" aria-labelledby="roi-title">
       <p class="eyebrow text-center grad-text mb-2">CALCULATEUR ROI</p>
       <h3 id="roi-title" class="text-2xl font-black text-center mb-6 text-brand-navy">Combien DictIA peut vous faire économiser&nbsp;?</h3>
       <div class="grid sm:grid-cols-3 gap-4 mb-6">
@@ -272,7 +272,7 @@
       </p>
     </div>
 
-    <div class="overflow-x-auto rounded-[18px] border border-brand-border">
+    <div class="overflow-x-auto rounded-xl border border-brand-border">
       <table class="w-full min-w-[720px] text-sm">
         <caption class="sr-only">Comparaison DictIA, Microsoft Teams Premium, Otter.ai Business, Whisper local sur 6 critères</caption>
         <thead class="bg-brand-bg">
@@ -390,8 +390,8 @@
           'desc': 'Architecture entièrement auditable sur <a href="https://gitea.innova-ai.ca/Innova-AI/dictia-public" target="_blank" rel="noopener" class="underline hover:text-white">Gitea public</a>. Aucune boîte noire. Vos auditeurs peuvent examiner chaque ligne.'
         }
       ] %}
-      <article class="bg-white/[0.05] backdrop-blur-sm p-6 rounded-[0.75rem] border border-white/[0.08]">
-        <div class="w-10 h-10 grad-bg rounded-[0.5rem] mb-4 flex items-center justify-center text-lg shadow-cta" aria-hidden="true">{{ card.icon }}</div>
+      <article class="bg-white/[0.05] backdrop-blur-sm p-6 rounded-lg border border-white/[0.08]">
+        <div class="w-10 h-10 grad-bg rounded-md mb-4 flex items-center justify-center text-lg shadow-cta" aria-hidden="true">{{ card.icon }}</div>
         <h3 class="text-lg font-bold mb-2 text-white">{{ card.title | safe }}</h3>
         <p class="text-sm text-white/80 leading-relaxed">{{ card.desc | safe }}</p>
       </article>
@@ -421,7 +421,7 @@
 
     <div class="grid md:grid-cols-3 gap-6">
       {% for t in testimonials %}
-      <article class="bg-white p-6 rounded-[18px] border border-brand-border flex flex-col items-center text-center"
+      <article class="bg-white p-6 rounded-xl border border-brand-border flex flex-col items-center text-center"
                aria-label="Témoignage {{ t.placeholder_label }} à venir">
         <div class="w-16 h-16 rounded-full grad-bg flex items-center justify-center mb-4 shadow-cta" aria-hidden="true">
           {%- if t.persona == 'avocat' -%}<span class="text-2xl">⚖️</span>