refactor(ui): V3 fully square buttons + inputs (rounded-none, brutalist/Swiss aesthetic)

V3 finalizes the radii pass to a fully brutalist/Swiss visual language:

- Buttons (CTAs, submit, secondary, ghost, OAuth provider tiles): rounded-none (0px)
- Form inputs (text/email/password/select/textarea/code-entry): rounded-none (0px)
- Checkboxes: rounded-none (0px) — was rounded-sm
- Small icon tiles (w-10 h-10 / w-12 h-12 grad-bg squares): rounded-none (0px)
- Inline code blocks (totp recovery <pre>, secret <code>): rounded-none (0px)
- Cards (pricing, bento, content panels, modals, prev/next nav): rounded (4px) — was rounded-lg
- Alert / flash boxes: rounded (4px) — was rounded-lg
- Pills, badges, status chips, ordres pros avatars, decorative cosmic orbs: rounded-full preserved
- Legal _layout.html inline <style> blockquote/pre/code/draft-callout: border-radius 0 — was 4px

Updated tests/test_marketing_landing_template.py assertions:
- bento icon assertion: "grad-bg rounded " -> "grad-bg rounded-none "
- pricing recommended frame: "rounded-lg" -> "rounded" (with strict trailing-char match to avoid rounded-none false positive)

Verification: 18/18 legal tests pass, 58/58 marketing landing tests pass, 5/5 root redirect tests pass. Two pre-existing failures in test_marketing_secondary_pages (SOC 2 hedge text + gitea.innova-ai.ca URL) are unrelated to this radii pass.

templates/legal/index.html

@@ -33,7 +33,7 @@
 
 {% block content %}
 <a href="#main-content"
-   class="sr-only focus:not-sr-only focus:fixed focus:top-2 focus:left-2 focus:z-[100] focus:px-4 focus:py-2 focus:bg-brand-navy focus:text-white focus:rounded focus-visible:outline-2 focus-visible:outline-brand-b1 focus-visible:outline-offset-2">
+   class="sr-only focus:not-sr-only focus:fixed focus:top-2 focus:left-2 focus:z-[100] focus:px-4 focus:py-2 focus:bg-brand-navy focus:text-white focus:rounded-none focus-visible:outline-2 focus-visible:outline-brand-b1 focus-visible:outline-offset-2">
   Aller au contenu principal
 </a>
 
@@ -68,13 +68,13 @@
           <a href="{{ page.url }}"
              target="_blank"
              rel="noopener noreferrer"
-             class="legal-card is-external group block h-full p-5 md:p-6 bg-white border border-brand-border rounded-lg hover:border-brand-b1 hover:shadow-cta focus-visible:outline-2 focus-visible:outline-brand-b1 focus-visible:outline-offset-2 relative">
+             class="legal-card is-external group block h-full p-5 md:p-6 bg-white border border-brand-border rounded hover:border-brand-b1 hover:shadow-cta focus-visible:outline-2 focus-visible:outline-brand-b1 focus-visible:outline-offset-2 relative">
         {% else %}
           <a href="{{ url_for('legal.legal_page', page=page.slug) }}"
-             class="legal-card group block h-full p-5 md:p-6 bg-white border border-brand-border rounded-lg hover:border-brand-b1 hover:shadow-cta focus-visible:outline-2 focus-visible:outline-brand-b1 focus-visible:outline-offset-2 relative">
+             class="legal-card group block h-full p-5 md:p-6 bg-white border border-brand-border rounded hover:border-brand-b1 hover:shadow-cta focus-visible:outline-2 focus-visible:outline-brand-b1 focus-visible:outline-offset-2 relative">
         {% endif %}
           <div class="flex items-start gap-4">
-            <div class="legal-card-icon shrink-0 inline-flex items-center justify-center w-12 h-12 rounded">
+            <div class="legal-card-icon shrink-0 inline-flex items-center justify-center w-12 h-12 rounded-none">
               {{ page.icon | safe }}
             </div>
             <div class="flex-1 min-w-0">
@@ -97,7 +97,7 @@
     </ul>
 
     {# Bloc info pied — signature, contact, sous-processeurs #}
-    <aside class="mt-12 max-w-3xl mx-auto bg-white border border-brand-border rounded-lg p-6 md:p-7"
+    <aside class="mt-12 max-w-3xl mx-auto bg-white border border-brand-border rounded p-6 md:p-7"
            aria-label="Informations complémentaires sur les documents légaux">
       <p class="text-sm text-brand-navy/80 leading-relaxed mb-3">
         Documents signés numériquement par <strong class="text-brand-navy">Allison Rioux</strong>,