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/auth/check_email.html

@@ -5,7 +5,7 @@
 
 {% block content %}
 <section class="min-h-[calc(100vh-62px)] bg-brand-bg py-16 px-4" aria-labelledby="check-email-title">
-  <div class="max-w-md mx-auto bg-white p-8 rounded-lg border border-brand-border shadow-cta text-center">
+  <div class="max-w-md mx-auto bg-white p-8 rounded border border-brand-border shadow-cta text-center">
     <div class="mx-auto mb-6 w-16 h-16 rounded-full grad-bg flex items-center justify-center text-white text-2xl" aria-hidden="true">&#x2709;</div>
 
     <h1 id="check-email-title" class="text-2xl font-black text-brand-navy mb-2">
@@ -30,7 +30,7 @@
     {% with messages = get_flashed_messages(with_categories=true) %}
       {% if messages %}
         {% for category, message in messages %}
-          <div role="alert" class="mb-3 p-3 rounded-lg text-sm
+          <div role="alert" class="mb-3 p-3 rounded text-sm
             {% if category == 'danger' %}bg-red-50 text-red-900 border border-red-200
             {% elif category == 'warning' %}bg-amber-50 text-amber-900 border border-amber-200
             {% elif category == 'success' %}bg-green-50 text-green-900 border border-green-200
@@ -45,7 +45,7 @@
       <form method="POST" action="{{ url_for('auth.resend_verification') }}" class="mb-4">
         <input type="hidden" name="csrf_token" value="{{ csrf_token() }}">
         <input type="hidden" name="email" value="{{ email }}">
-        <button type="submit" class="w-full grad-bg text-white font-semibold py-3 rounded shadow-cta hover:shadow-cta-hover transition focus-visible:outline-2 focus-visible:outline-brand-b1 focus-visible:outline-offset-2">
+        <button type="submit" class="w-full grad-bg text-white font-semibold py-3 rounded-none shadow-cta hover:shadow-cta-hover transition focus-visible:outline-2 focus-visible:outline-brand-b1 focus-visible:outline-offset-2">
           Renvoyer le lien de vérification
         </button>
       </form>