fix(i18n): формальный русский перевод + t() во всех шаблонах

- i18n.py: формальный русский (сканирования, панель управления, и т.д.)
- Все шаблоны: замена хардкод-строк на t(key, request.state.lang)
- dashboard_stats_fragment: добавлен request в контекст

guarddog_nexus/web/templates/dashboard_stats.html

@@ -1,8 +1,8 @@
 {% if latest_flagged %}
 <article class="dash-block dash-block-warn">
-    <h3>Latest Flagged</h3>
+    <h3>{{ t('heading_latest_flagged', request.state.lang) }}</h3>
     <table class="compact">
-        <thead><tr><th>Package</th><th>Version</th><th>Findings</th><th>Time</th></tr></thead>
+        <thead><tr><th>{{ t('col_package', request.state.lang) }}</th><th>{{ t('col_version', request.state.lang) }}</th><th>{{ t('col_findings', request.state.lang) }}</th><th>{{ t('col_time', request.state.lang) }}</th></tr></thead>
         <tbody>
         {% for s in latest_flagged %}
             <tr>
@@ -18,10 +18,10 @@
 {% endif %}
 
 <article class="dash-block" style="margin-top: 0;">
-    <h3>Latest Scans</h3>
+    <h3>{{ t('heading_latest_scans', request.state.lang) }}</h3>
     <table class="compact">
         <thead>
-            <tr><th>Package</th><th>Version</th><th>Repo</th><th>Status</th><th></th><th>Time</th></tr>
+            <tr><th>{{ t('col_package', request.state.lang) }}</th><th>{{ t('col_version', request.state.lang) }}</th><th>{{ t('col_repo', request.state.lang) }}</th><th>{{ t('col_status', request.state.lang) }}</th><th></th><th>{{ t('col_time', request.state.lang) }}</th></tr>
         </thead>
         <tbody>
         {% for s in latest_scans %}
@@ -38,7 +38,7 @@
         {% endfor %}
         </tbody>
     </table>
-    <small><a href="/scans">View all scans →</a></small>
+    <small><a href="/scans">{{ t('view_all_scans', request.state.lang) }}</a></small>
 </article>
 
-<small style="opacity: 0.4;">Last refresh: {{ now.strftime('%H:%M:%S') }} (auto every 30s)</small>
+<small style="opacity: 0.4;">{{ t('refresh_hint', request.state.lang, now.strftime('%H:%M:%S')) }}</small>