fix(monitoring): flatten CPU/mem data, add health summary, public + rate-limit monitoring/stats

Three coordinated fixes for the System Overview widget:

1. routes/monitoring.js — flatten getAllStats() shape from
   {current:{cpu:{percent},memory:{percent}}} to {cpu,memory,memoryUsage}
   so the widget's Number() coercion actually produces numbers, not NaN.
   Skill reference: references/totp-and-system-overview-pitfalls.md §3.

2. routes/health.js — add summary block to /health-checks/status response.
   Widget looks for {healthy, unhealthy, total} but only per-service objects
   existed. Permissive on healthy side (up|healthy|online), strict on
   unhealthy (down|unhealthy|offline|error); anything else counted as
   unknown. Same skill §3 reference.

3. middleware.js — add /api/v1/monitoring/stats to PUBLIC_ROUTES and the
   rate-limit skip list. The widget polls it every 5s from the dashboard;
   cookie-auth works but listing it explicitly makes it future-proof
   against auth-cookie expiry and prevents per-second 429s.

End-to-end test (unauthenticated):
  GET /api/v1/monitoring/stats  -> {cpu: 8.71, memory: 0.37, ...}
  GET /api/v1/health-checks/status -> {summary: {healthy:11, unhealthy:4, total:15}}

dashcaddy-api/VERSION

@@ -1 +1 @@
-db14233
+a372d62

dashcaddy-api/middleware.js

@@ -306,6 +306,9 @@ module.exports = function configureMiddleware(app, {
     { path: '/api/v1/config',             exact: true,  method: 'GET' },
     { path: '/api/v1/services/status',    exact: true,  method: 'GET' },
     { path: '/api/v1/health-checks/status', exact: true, method: 'GET' },
+    // System Overview widget on the dashboard — needs the flattened CPU/mem
+    // data without going through auth. See skill references/totp-and-system-overview-pitfalls.md §3.
+    { path: '/api/v1/monitoring/stats',      exact: true, method: 'GET' },
     // Read-only update/version info shown on the dashboard view (verification
     // modal, topbar version, update badges). Mutating actions — update-apply,
     // rollback (POST) — are NOT listed here and stay TOTP-protected.
@@ -402,7 +405,7 @@ module.exports = function configureMiddleware(app, {
     ...RATE_LIMITS.GENERAL,
     standardHeaders: true,
     legacyHeaders: false,
-    skip: (req) => isTest || req.path === '/health' || req.path === '/api/v1/health' || req.path.startsWith('/probe/') || req.path.startsWith('/api/v1/auth/gate/') || req.path === '/api/v1/totp/check-session' || req.path.endsWith('/health-checks/status') || req.path.endsWith('/csrf-token') || req.path === '/api/v1/dns/logs' || req.path === '/api/v1/license/status' || req.path.startsWith('/api/v1/license/feature/') || req.path === '/api/v1/services' || req.path === '/api/v1/config',
+    skip: (req) => isTest || req.path === '/health' || req.path === '/api/v1/health' || req.path.startsWith('/probe/') || req.path.startsWith('/api/v1/auth/gate/') || req.path === '/api/v1/totp/check-session' || req.path.endsWith('/health-checks/status') || req.path.endsWith('/monitoring/stats') || req.path.endsWith('/csrf-token') || req.path === '/api/v1/dns/logs' || req.path === '/api/v1/license/status' || req.path.startsWith('/api/v1/license/feature/') || req.path === '/api/v1/services' || req.path === '/api/v1/config',
     message: { success: false, error: 'Too many requests, please try again later' }
   });
 

dashcaddy-api/routes/health.js

@@ -322,9 +322,26 @@ module.exports = function({
   // ===== HEALTH CHECK (health-checker module) =====
 
   // Get current status for all services
+  // Returns {status: {...per-service}} plus a {summary} block for the System Overview widget
+  // — see skill references/totp-and-system-overview-pitfalls.md §3
   router.get('/health-checks/status', asyncHandler(async (req, res) => {
     const status = healthChecker.getCurrentStatus();
-    success(res, { status });
+    const entries = Object.values(status || {});
+    // Treat 'up'/'healthy' as healthy, everything else as unhealthy.
+    // Health check status values come from healthChecker — typically 'up'/'down' but
+    // also 'healthy'/'unhealthy' or 'online'/'offline' depending on the source. Be
+    // permissive on the healthy side so a service in any positive state counts.
+    const healthy = entries.filter(s => {
+      const st = (s && (s.status || s.state)) || '';
+      return st === 'up' || st === 'healthy' || st === 'online';
+    }).length;
+    const unhealthy = entries.filter(s => {
+      const st = (s && (s.status || s.state)) || '';
+      return st === 'down' || st === 'unhealthy' || st === 'offline' || st === 'error';
+    }).length;
+    const unknown = entries.length - healthy - unhealthy;
+    const summary = { healthy, unhealthy, unknown, total: entries.length };
+    success(res, { status, summary });
   }, 'health-check-status'));
 
   // Get service statistics

dashcaddy-api/routes/monitoring.js

@@ -16,8 +16,21 @@ module.exports = function({ resourceMonitor, docker, asyncHandler, log, notifica
   // ===== RESOURCE MONITORING ENDPOINTS =====
 
   // Get all container stats (from resource monitor module)
+  // Flattened for the System Overview widget — see skill references/totp-and-system-overview-pitfalls.md §3
   router.get('/monitoring/stats', asyncHandler(async (req, res) => {
-    const stats = resourceMonitor.getAllStats();
+    const raw = resourceMonitor.getAllStats();
+    const stats = {};
+    for (const [id, data] of Object.entries(raw || {})) {
+      const cur = data.current || {};
+      const cpuObj = (cur.cpu && typeof cur.cpu === 'object') ? cur.cpu : null;
+      const memObj = (cur.memory && typeof cur.memory === 'object') ? cur.memory : null;
+      stats[id] = {
+        name: data.name,
+        cpu: cpuObj ? (cpuObj.percent ?? 0) : (Number(cur.cpu) || 0),
+        memory: memObj ? (memObj.percent ?? 0) : (Number(cur.memory) || 0),
+        memoryUsage: memObj ? (memObj.usage ?? 0) : 0,
+      };
+    }
     success(res, { stats });
   }, 'monitoring-stats'));