Standardize response shapes and fix dead fetchT timeout keys

Three small cleanups for v1.14.0:

1. /caddy/cas now uses standard success envelope
   Was: { status: 'success', data: { cas: caList } }
   Now: { success: true, cas: caList }
   Updated frontend service-infrastructure.js to match.

2. /api/health/ca now uses standard envelope + meaningful HTTP codes
   Was: { status, message, daysUntilExpiration } with 200 on every error
   Now: { success, caStatus, message|error, daysUntilExpiration }
        with 200 / 404 / 500 as appropriate
   caStatus field preserves the original 'healthy'/'warning'/'critical'/'error'
   semantic so any future consumer of the CA-health state still has it.
   Tests updated to match.

3. Dead timeout: keys in fetchT opts are now a warning, not a silent strip
   src/utils/http.js:41 used to do  without telling
   anyone. Callers that wrote fetchT(url, { timeout: 5000 }) got the default
   5s timeout with no indication that their explicit value was ignored.
   Now it logs a warning naming the call site, then strips the key.
   Fixed 4 call sites that had stale timeout: keys:
   - src/context/caddy.js
   - src/context/dns.js
   - src/context/provider-dns.js
   - routes/dns.js (2 places)

dashcaddy-api/routes/dns.js

@@ -383,9 +383,8 @@ module.exports = function({
 
       const response = await fetchT(technitiumUrl, {
         method: 'GET',
-        headers: { 'Accept': 'text/plain' },
-        timeout: 10000
-      });
+        headers: { 'Accept': 'text/plain' }
+      }, 10000);
 
       if (!response.ok) {
         const errorText = await response.text();
@@ -640,7 +639,7 @@ module.exports = function({
     const dnsPort = siteConfig.dnsServerPort || '5380';
     try {
       const url = `http://${serverInfo.ip}:${dnsPort}/api/admin/restart?token=${encodeURIComponent(tokenResult.token)}`;
-      const response = await fetchT(url, { method: 'POST', timeout: 5000 });
+      const response = await fetchT(url, { method: 'POST' }, 5000);
       const result = await response.json();
       if (result.status === 'ok') {
         success(res, { message: 'Restart initiated' });