v1.9.1: Admin UI - Section Reseau Tailscale (statut, IP, hostname, logs)

- admin.html: nouveau card 'Reseau Tailscale' avec statut connecte/deconnecte,
  IP tailnet, hostname, serveur Headscale et bouton Actualiser
- admin.html: bloc deroulant pour consulter les 50 dernieres lignes du log
  bootstrap (logs/tailscale_bootstrap.log)
- launcher.php: nouvelles actions get_tailscale_info (status + IP + hostname
  via sudo tailscale ip/status) et get_tailscale_log (tail -n 50)

Complete la v1.9.0 avec la visibilite UI necessaire pour valider/diagnostiquer
la connexion Tailscale sur chaque capteur sans avoir a passer en SSH.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

html/admin.html

@@ -339,6 +339,45 @@
 
         </div>
 
+        <!-- TAILSCALE SECTION -->
+        <div class="row mb-3">
+          <div class="col-lg-8 col-12">
+            <h4 class="mt-4">Réseau Tailscale</h4>
+            <div id="tailscale-card" class="card">
+              <div class="card-header d-flex justify-content-between align-items-center">
+                <span class="fw-bold">État de la connexion au tailnet AirCarto</span>
+                <button type="button" class="btn btn-sm btn-outline-primary" onclick="refreshTailscaleInfo()">
+                  <svg width="14" height="14" fill="currentColor" class="bi bi-arrow-clockwise" viewBox="0 0 16 16">
+                    <path fill-rule="evenodd" d="M8 3a5 5 0 1 0 4.546 2.914.5.5 0 0 1 .908-.417A6 6 0 1 1 8 2v1z"/>
+                    <path d="M8 4.466V.534a.25.25 0 0 1 .41-.192l2.36 1.966c.12.1.12.284 0 .384L8.41 4.658A.25.25 0 0 1 8 4.466z"/>
+                  </svg>
+                  Actualiser
+                </button>
+              </div>
+              <div class="card-body">
+                <dl class="row mb-2">
+                  <dt class="col-sm-3 text-muted">Statut</dt>
+                  <dd class="col-sm-9"><span id="tailscaleStatus" class="badge bg-secondary">Chargement…</span></dd>
+
+                  <dt class="col-sm-3 text-muted">IP tailnet</dt>
+                  <dd class="col-sm-9"><code id="tailscaleIp">—</code></dd>
+
+                  <dt class="col-sm-3 text-muted">Hostname</dt>
+                  <dd class="col-sm-9"><code id="tailscaleHostname">—</code></dd>
+
+                  <dt class="col-sm-3 text-muted">Serveur</dt>
+                  <dd class="col-sm-9"><code id="tailscaleLoginServer">—</code></dd>
+                </dl>
+                <div id="tailscaleMessage" class="alert alert-warning small mb-2" style="display: none;"></div>
+                <details>
+                  <summary class="text-muted small" style="cursor: pointer;">Logs bootstrap (cliquer pour ouvrir)</summary>
+                  <pre id="tailscaleLog" class="mb-0 mt-2" style="max-height: 250px; overflow-y: auto; font-size: 0.8rem; background-color: #f8f9fa; padding: 0.75rem; border-radius: 0.375rem;">Chargement…</pre>
+                </details>
+              </div>
+            </div>
+          </div>
+        </div>
+
         <!-- SYSTEMD SERVICES SECTION -->
         <div class="row mb-3">
           <div class="col-lg-8 col-12">
@@ -702,6 +741,9 @@ window.onload = function() {
   // Load firmware version
   loadFirmwareVersion();
 
+  // Load Tailscale connection info
+  refreshTailscaleInfo();
+
 } //end window.onload
 
 
@@ -2225,6 +2267,73 @@ function loadFirmwareVersion() {
   });
 }
 
+function refreshTailscaleInfo() {
+  $.ajax({
+    url: 'launcher.php?type=get_tailscale_info',
+    dataType: 'json',
+    method: 'GET',
+    cache: false,
+    success: function(response) {
+      const statusBadge = document.getElementById('tailscaleStatus');
+      const ipEl = document.getElementById('tailscaleIp');
+      const hostEl = document.getElementById('tailscaleHostname');
+      const serverEl = document.getElementById('tailscaleLoginServer');
+      const msgEl = document.getElementById('tailscaleMessage');
+
+      serverEl.textContent = response.login_server || '—';
+
+      if (!response.installed) {
+        statusBadge.textContent = 'Non installé';
+        statusBadge.className = 'badge bg-secondary';
+        ipEl.textContent = '—';
+        hostEl.textContent = '—';
+        msgEl.style.display = 'block';
+        msgEl.textContent = response.message || 'Tailscale non installé.';
+      } else if (response.connected) {
+        statusBadge.textContent = '✓ Connecté';
+        statusBadge.className = 'badge bg-success';
+        ipEl.textContent = response.ip || '—';
+        hostEl.textContent = response.hostname || '—';
+        msgEl.style.display = 'none';
+      } else {
+        statusBadge.textContent = '✗ Déconnecté';
+        statusBadge.className = 'badge bg-danger';
+        ipEl.textContent = '—';
+        hostEl.textContent = '—';
+        msgEl.style.display = 'block';
+        msgEl.textContent = "Tailscale est installé mais n'est pas connecté au tailnet. Vérifier le log bootstrap ci-dessous ou relancer un Update firmware.";
+      }
+
+      refreshTailscaleLog();
+    },
+    error: function() {
+      const statusBadge = document.getElementById('tailscaleStatus');
+      statusBadge.textContent = 'Erreur';
+      statusBadge.className = 'badge bg-warning';
+    }
+  });
+}
+
+function refreshTailscaleLog() {
+  $.ajax({
+    url: 'launcher.php?type=get_tailscale_log',
+    dataType: 'json',
+    method: 'GET',
+    cache: false,
+    success: function(response) {
+      const logEl = document.getElementById('tailscaleLog');
+      if (response.success && response.log) {
+        logEl.textContent = response.log;
+      } else {
+        logEl.textContent = response.message || '(log vide)';
+      }
+    },
+    error: function() {
+      document.getElementById('tailscaleLog').textContent = '(erreur de chargement du log)';
+    }
+  });
+}
+
 function showChangelogModal() {
   const modal = new bootstrap.Modal(document.getElementById('changelogModal'));
   modal.show();