feat: proactive alerts, Jellyfin control, agent sparklines, CCR roster fix

- Proactive alerts (#1): polls every 60s; baselines on load so old alerts are silent; speaks new critical/warning alerts aloud if voice active; adds chat bubble for all new alerts
- Jellyfin control (#2): pause/stop/next/previous via voice — auto-detects active session; 12 KB intents; jellyfin.php control action uses Jellyfin General Commands API
- Agent sparklines (#6): metrics.php returns 2h CPU+MEM history per agent; SVG polyline sparklines rendered in each agent card (cyan=CPU, green=MEM); non-blocking fetch so existing view shows instantly
- Agent health CCR (#7): updated hourly cloud routine to current 13-agent roster, removed ollama-ai and alien-pc, added all active agents with correct IPs/IDs

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

api/endpoints/chat.php

@@ -1722,6 +1722,46 @@ if (!$reply) {
                 $source = 'intent:network_scan';
                 break;
 
+            case 'jellyfin_pause':
+            case 'jellyfin_stop':
+            case 'jellyfin_next':
+            case 'jellyfin_previous': {
+                $intentCmd = [
+                    'jellyfin_pause'    => 'TogglePause',
+                    'jellyfin_stop'     => 'Stop',
+                    'jellyfin_next'     => 'NextTrack',
+                    'jellyfin_previous' => 'PreviousTrack',
+                ][$matched['intent']];
+                // Get first active session
+                $jfSessions = @json_decode(@file_get_contents(
+                    JELLYFIN_URL . '/Sessions?api_key=' . JELLYFIN_API_KEY, false,
+                    stream_context_create(['http' => ['timeout' => 4]])
+                ), true) ?? [];
+                $activeSession = null;
+                foreach ($jfSessions as $s) {
+                    if (isset($s['NowPlayingItem'])) { $activeSession = $s; break; }
+                }
+                if (!$activeSession) {
+                    $reply  = "Nothing is currently playing on Jellyfin, {$userAddr}.";
+                } else {
+                    $sid    = $activeSession['Id'];
+                    $url    = JELLYFIN_URL . '/Sessions/' . rawurlencode($sid) . '/Command/' . $intentCmd
+                            . '?api_key=' . JELLYFIN_API_KEY;
+                    $ctx    = stream_context_create(['http' => ['method' => 'POST', 'timeout' => 5,
+                                'header' => 'Content-Type: application/json', 'content' => '{}', 'ignore_errors' => true]]);
+                    @file_get_contents($url, false, $ctx);
+                    $titles = [
+                        'TogglePause'    => 'Playback toggled, {$userAddr}.',
+                        'Stop'           => 'Playback stopped, {$userAddr}.',
+                        'NextTrack'      => 'Skipping to next track, {$userAddr}.',
+                        'PreviousTrack'  => 'Going back to previous, {$userAddr}.',
+                    ];
+                    $reply = strtr($titles[$intentCmd], ['{$userAddr}' => $userAddr]);
+                }
+                $source = 'intent:jellyfin_control';
+                break;
+            }
+
             case 'jellyfin_now_playing':
                 $jSessions = @json_decode(@file_get_contents(
                     JELLYFIN_URL . '/Sessions?api_key=' . JELLYFIN_API_KEY, false,