feat: add allow insecure connections toggle in system settings

Block ws:// relay connections and http:// resource loading by default
to prevent browser mixed content warnings. When blocked, resources
show clickable URL links instead of error placeholders so users can
open them manually.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/pages/secondary/SystemSettingsPage/index.tsx

@@ -16,6 +16,9 @@ const SystemSettingsPage = forwardRef(({ index }: { index?: number }, ref) => {
   const [filterOutOnionRelays, setFilterOutOnionRelays] = useState(
     storage.getFilterOutOnionRelays()
   )
+  const [allowInsecureConnection, setAllowInsecureConnection] = useState(
+    storage.getAllowInsecureConnection()
+  )
 
   return (
     <SecondaryPageLayout ref={ref} index={index} title={t('System')}>
@@ -45,6 +48,22 @@ const SystemSettingsPage = forwardRef(({ index }: { index?: number }, ref) => {
             }}
           />
         </div>
+        <div className="flex min-h-9 items-center justify-between px-4">
+          <Label htmlFor="allow-insecure-connection" className="text-base font-normal">
+            <div>{t('Allow insecure connections')}</div>
+            <div className="text-muted-foreground">
+              {t('Allow insecure connections description')}
+            </div>
+          </Label>
+          <Switch
+            id="allow-insecure-connection"
+            checked={allowInsecureConnection}
+            onCheckedChange={(checked) => {
+              storage.setAllowInsecureConnection(checked)
+              setAllowInsecureConnection(checked)
+            }}
+          />
+        </div>
         <div className="space-y-2 px-4">
           <DefaultRelaysSetting />
         </div>