Phase 5: Guardian Mode — continuous awareness + proactive AI alerts

- reactor.py: v5.0.0; guardian_loop() background task scans all agents every
  120s; checks CPU/mem/disk thresholds + agent offline transitions + failed
  services; 10min cooldown per metric to debounce repeat alerts; AI analysis
  of critical findings via Claude; proactive chat injection into conversations
  table; handle_sitrep() generates Iron Man-style full/brief situation reports;
  handle_guardian_config() reads/writes guardian_config table; FastAPI endpoints:
  /guardian/status, /guardian/events, /guardian/events/{id}/ack, /guardian/chat
- arc.php: guardian_status, guardian_events, guardian_ack, guardian_chat actions
- chat.php: Tier 0.9d detects sitrep/situation report/how are things commands
- index.html: GUARDIAN tab in right panel; guardian event list with severity
  badges + AI analysis; ACK / ACK ALL buttons; Guardian badge in bottom bar
  (green/amber/red pulse based on unread critical events); proactive chat
  polling every 30s surfacing guardian-injected messages as JARVIS speech
- admin/index.php: GUARDIAN MODE tab; status bar + events table + config modal;
  inline SITREP runner with result modal; threshold configuration

api/endpoints/arc.php

@@ -179,6 +179,40 @@ switch ($action) {
         echo json_encode(arc_request('DELETE', "/screenshots/{$id}"));
         break;
 
+    // ── GUARDIAN MODE ─────────────────────────────────────────────────────────
+    case 'guardian_status':
+        echo json_encode(arc_request('GET', '/guardian/status'));
+        break;
+
+    case 'guardian_events':
+        $limit    = (int)($_GET['limit'] ?? 30);
+        $unread   = !empty($_GET['unread']) ? 'true' : '';
+        $severity = $_GET['severity'] ?? '';
+        $since    = $_GET['since'] ?? '';
+        $qs = http_build_query(array_filter([
+            'limit'    => $limit,
+            'unread'   => $unread,
+            'severity' => $severity,
+            'since'    => $since,
+        ]));
+        echo json_encode(arc_request('GET', '/guardian/events' . ($qs ? "?{$qs}" : '')));
+        break;
+
+    case 'guardian_ack':
+        $id = (int)($_GET['id'] ?? $data['id'] ?? 0);
+        if ($id) {
+            echo json_encode(arc_request('POST', "/guardian/events/{$id}/ack"));
+        } else {
+            echo json_encode(arc_request('POST', '/guardian/events/ack_all'));
+        }
+        break;
+
+    case 'guardian_chat':
+        $since = $_GET['since'] ?? '';
+        $qs    = $since ? '?since=' . urlencode($since) : '';
+        echo json_encode(arc_request('GET', '/guardian/chat' . $qs));
+        break;
+
     default:
         http_response_code(404);
         echo json_encode(['error' => "Unknown arc action: {$action}"]);

api/endpoints/chat.php

@@ -1190,6 +1190,35 @@ if (!$reply) {
     }
 }
 
+// ── Tier 0.9d: Guardian Mode — sitrep detection ───────────────────────────
+if (!$reply) {
+    $sitrepPatterns = [
+        '/^(?:jarvis[,\s]+)?(?:sitrep|sit\s+rep|situation\s+report|status\s+report)/i',
+        '/^(?:jarvis[,\s]+)?(?:give\s+me\s+a|run\s+a)\s+(?:sitrep|situation|status)\s*(?:report)?/i',
+        '/^(?:jarvis[,\s]+)?(?:how\s+(?:are|is)\s+(?:everything|all\s+systems?|things?)(?:\s+looking)?)/i',
+        '/^(?:jarvis[,\s]+)?(?:system\s+health|overall\s+status|all\s+systems\s+(?:check|status|go))/i',
+        '/^(?:jarvis[,\s]+)?what(?:\'s|\s+is)\s+(?:the\s+)?overall\s+(?:system\s+)?status/i',
+    ];
+    $isSimple = (bool) preg_match('/\b(?:brief|quick|short|summary)\b/i', $message);
+    foreach ($sitrepPatterns as $pat) {
+        if (preg_match($pat, $message)) {
+            $arcRes = arcSubmitJob('sitrep', [
+                'detail'   => $isSimple ? 'brief' : 'full',
+                'provider' => 'claude',
+            ], $sessionId);
+            if (isset($arcRes['job_id'])) {
+                $arcJobId = $arcRes['job_id'];
+                $reply  = "◈ GUARDIAN PROTOCOL — Generating situation report (Job #{$arcJobId}). Scanning all field stations and synthesizing a briefing now, {$userAddr}. Stand by.";
+                $source = 'arc:sitrep';
+            } else {
+                $reply  = "Guardian Protocol is offline, {$userAddr}. Arc Reactor may be unavailable.";
+                $source = 'arc:offline';
+            }
+            break;
+        }
+    }
+}
+
 // ── Tier 0.9e: Intel Protocol — research & tool_loop detection ────────────
 $intelPatterns = [
     '/^(?:jarvis[,\s]+)?(?:research|investigate|deep[- ]dive|deep dive)\s+(.+)/i' => 'research',