Add EN/UK/PL translations across index, footer, and why-ours pages

- index.php: translate hardcoded hero kicker, stat, explore CTA, tools
  section title/sub, and learn-more arrow; add Pricing nav link
- footer.php: fully translate tagline, privacy note, nav links, and
  disclaimer into all 4 languages via dbnToolsT()
- includes/i18n.php: 15 new keys per language (hero_kicker, footer_*,
  tools_section_*, pricing_nav_link, why_ours_trust_link, learn_more)
- translations/why-ours.php: complete uk + pl translations (70 keys each)
- assets/css/tools.css: add .lt-nav__secondary-link style

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

includes/footer.php

@@ -1,4 +1,10 @@
-<?php declare(strict_types=1); ?>
+<?php
+declare(strict_types=1);
+$_footerLang = dbnToolsCurrentLanguage();
+function _ft(string $key, string $lang): string {
+    return htmlspecialchars(dbnToolsT($key, $lang));
+}
+?>
 <footer class="lt-footer">
   <div class="lt-footer__inner">
 
@@ -8,23 +14,24 @@
         <img class="lt-footer__logo" src="assets/images/logo-header.png" alt="Do Better Norge" width="140" height="34" loading="lazy">
       </picture>
       <p class="lt-footer__tagline">
-        AI legal tools for families navigating Norwegian child-welfare cases.
-        Powered by <a href="https://bluenotelogic.com/caveauai" target="_blank" rel="noopener noreferrer">CaveauAI</a>.
+        <?= _ft('footer_tagline', $_footerLang) ?>
+        <?= $_footerLang === 'no' ? 'Drevet av' : 'Powered by' ?> <a href="https://bluenotelogic.com/caveauai" target="_blank" rel="noopener noreferrer">CaveauAI</a>.
       </p>
       <p class="lt-footer__privacy-note">
-        Your documents are processed in memory and discarded when your session ends.
-        Nothing is stored or retained.
+        <?= _ft('footer_privacy_note', $_footerLang) ?>
       </p>
     </div>
 
     <nav class="lt-footer__links" aria-label="Footer links">
       <div class="lt-footer__link-col">
         <a href="https://dobetternorge.no" target="_blank" rel="noopener noreferrer">Do Better Norge</a>
-        <a href="https://dobetternorge.no/library.php">Legal library</a>
-        <a href="mailto:support@dobetternorge.no">Report an issue</a>
+        <a href="https://dobetternorge.no/library.php"><?= _ft('footer_legal_lib', $_footerLang) ?></a>
+        <a href="/pricing.php"><?= _ft('pricing_nav_link', $_footerLang) ?></a>
+        <a href="/why-ours.php"><?= _ft('why_ours_trust_link', $_footerLang) ?></a>
+        <a href="mailto:support@dobetternorge.no"><?= _ft('footer_report', $_footerLang) ?></a>
       </div>
       <div class="lt-footer__link-col">
-        <a href="https://bluenotelogic.com/caveauai" target="_blank" rel="noopener noreferrer">About CaveauAI</a>
+        <a href="https://bluenotelogic.com/caveauai" target="_blank" rel="noopener noreferrer"><?= _ft('footer_about_caveau', $_footerLang) ?></a>
         <a href="https://bluenotelogic.com" target="_blank" rel="noopener noreferrer">Blue Note Logic</a>
       </div>
     </nav>
@@ -32,6 +39,6 @@
   </div>
   <div class="lt-footer__bottom">
     <p class="lt-footer__copy">&copy; 2026 Blue Note Logic Inc. All rights reserved.</p>
-    <p class="lt-footer__disclaimer">AI output is for advocacy support only &mdash; not legal advice. Always verify with a licensed Norwegian lawyer.</p>
+    <p class="lt-footer__disclaimer"><?= _ft('footer_disclaimer', $_footerLang) ?></p>
   </div>
 </footer>