feat(images): JPEG XL optimizer with webp/jpg fallback and <picture> serving

img_optimize() decodes .jxl with djxl or Imagick, resizes with GD, re-encodes
with cjxl and writes foto.jxl.webp beside it; skips cleanly without a decoder.
Gallery, hero, navbar logos and JSON-LD serve the JXL with the fallback, and
trash/removal move the fallback with its .jxl.

views/admin/gyms/_form.php

@@ -43,7 +43,7 @@ foreach (array_keys(gym_sections()) as $k) if (gym_section_on($data, $k)) $secti
     <div class="col-md-6">
         <label class="form-label" for="hero_file">Imagem do header</label>
         <?php if (($data['hero_image'] ?? '') !== ''): ?>
-        <div class="mb-2"><img src="<?= htmlspecialchars(base_url($data['hero_image'])) ?>" alt="" class="rounded border" style="max-width:100%;max-height:110px;object-fit:cover"></div>
+        <div class="mb-2"><img src="<?= htmlspecialchars(base_url(img_compat_rel($data['hero_image']))) ?>" alt="" class="rounded border" style="max-width:100%;max-height:110px;object-fit:cover"></div>
         <?php endif; ?>
         <input type="hidden" name="hero_image" value="<?= htmlspecialchars($data['hero_image'] ?? '') ?>">
         <input type="file" class="form-control" id="hero_file" name="hero_file" accept="image/jpeg,image/png,image/webp,image/jxl,.jxl">