Redact API keys from error technical-details disclosure

SABnzbd and Tautulli embed their API key in the request URL, so it
was showing up verbatim in the raw exception text under "Technical
details" on the dashboard — visible to anyone with the study-room
password. Added a redact_secrets filter that strips apikey/token/
password query params before the raw string is rendered.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

templates/dashboard.html

@@ -980,7 +980,7 @@
     {% if raw %}
     <details class="error-detail">
       <summary>Technical details</summary>
-      <pre>{{ raw }}</pre>
+      <pre>{{ raw | redact_secrets }}</pre>
     </details>
     {% endif %}
   </div>