perf: add defer to scripts and lazy loading to images

Add defer attribute to 145 <script> tags across 103 template files
(PERF-067) and loading="lazy" to 22 <img> tags across 13 template
files (PERF-058). Both improve page load performance.

Validator totals: 0 errors, 2 warnings, 1360 info (down from 1527).

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

app/modules/cms/templates/cms/admin/content-page-edit.html

@@ -636,5 +636,5 @@
 {% endblock %}
 
 {% block extra_scripts %}
-<script src="{{ url_for('cms_static', path='admin/js/content-page-edit.js') }}"></script>
+<script defer src="{{ url_for('cms_static', path='admin/js/content-page-edit.js') }}"></script>
 {% endblock %}

app/modules/cms/templates/cms/admin/content-pages.html

@@ -178,5 +178,5 @@
 {% endblock %}
 
 {% block extra_scripts %}
-<script src="{{ url_for('cms_static', path='admin/js/content-pages.js') }}"></script>
+<script defer src="{{ url_for('cms_static', path='admin/js/content-pages.js') }}"></script>
 {% endblock %}

app/modules/cms/templates/cms/store/content-page-edit.html

@@ -322,5 +322,5 @@
 {% endblock %}
 
 {% block extra_scripts %}
-<script src="{{ url_for('cms_static', path='store/js/content-page-edit.js') }}"></script>
+<script defer src="{{ url_for('cms_static', path='store/js/content-page-edit.js') }}"></script>
 {% endblock %}

app/modules/cms/templates/cms/store/content-pages.html

@@ -323,5 +323,5 @@
 {% endblock %}
 
 {% block extra_scripts %}
-<script src="{{ url_for('cms_static', path='store/js/content-pages.js') }}"></script>
+<script defer src="{{ url_for('cms_static', path='store/js/content-pages.js') }}"></script>
 {% endblock %}

app/modules/cms/templates/cms/store/media.html

@@ -321,7 +321,7 @@
                 <!-- Preview -->
                 <div class="bg-gray-100 dark:bg-gray-700 rounded-lg overflow-hidden">
                     <template x-if="selectedMedia?.media_type === 'image'">
-                        <img :src="selectedMedia?.file_url" :alt="selectedMedia?.original_filename" class="w-full h-auto">
+                        <img loading="lazy" :src="selectedMedia?.file_url" :alt="selectedMedia?.original_filename" class="w-full h-auto">
                     </template>
                     <template x-if="selectedMedia?.media_type !== 'image'">
                         <div class="aspect-square flex items-center justify-center text-gray-400">
@@ -441,5 +441,5 @@
 {% endblock %}
 
 {% block extra_scripts %}
-<script src="{{ url_for('cms_static', path='store/js/media.js') }}"></script>
+<script defer src="{{ url_for('cms_static', path='store/js/media.js') }}"></script>
 {% endblock %}