Fix AI tab save: dedicated AJAX endpoint /save-ai

Instead of relying on the native HTML form (which couldn't reliably
isolate AI fields), the IA tab now uses an AJAX call identical to
save-per-type. The new /admin/bot-config/save-ai endpoint only
reads and merges AI fields into config_json, preserving menus/flows.

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

admin/DashboardController.php

@@ -3747,7 +3747,7 @@ HTML;
           <strong>Requiere bot_type = hybrid y proveedor de IA configurado.</strong>
         </div>
       </div>
-      <div style="margin-top:14px"><button type="submit" class="btn-primary">💾 Guardar IA</button></div>
+      <div style="margin-top:14px"><button type="button" id="saveAiBtn" onclick="saveAiConfig()" class="btn-primary">💾 Guardar IA</button></div>
     </div>
 
     <!-- ─── GENERAL ──────────────────────────────────────────────────────── -->
@@ -3842,6 +3842,41 @@ function savePerType() {
     });
 }
 
+function saveAiConfig() {
+  const cid = document.querySelector('input[name="company_id"]').value;
+  const fd  = new FormData();
+  fd.set('company_id', cid);
+  const qs = sel => document.querySelector(sel);
+  fd.set('ai_provider',    qs('select[name="ai_provider"]')?.value    || '');
+  fd.set('ai_model',       qs('select[name="ai_model"]')?.value        || 'gpt-4o-mini');
+  fd.set('ai_temperature', qs('input[name="ai_temperature"]')?.value   || '0.7');
+  fd.set('ai_prompt',      qs('textarea[name="ai_prompt"]')?.value     || '');
+  fd.set('gemini_model',   qs('select[name="gemini_model"]')?.value    || '');
+  fd.set('claude_model',   qs('select[name="claude_model"]')?.value    || '');
+  const oKey = qs('input[name="openai_api_key"]')?.value || '';
+  const gKey = qs('input[name="gemini_api_key"]')?.value || '';
+  const cKey = qs('input[name="claude_api_key"]')?.value || '';
+  if (oKey) fd.set('openai_api_key', oKey);
+  if (gKey) fd.set('gemini_api_key', gKey);
+  if (cKey) fd.set('claude_api_key', cKey);
+  if (qs('input[name="ai_for_media"]')?.checked) fd.set('ai_for_media', '1');
+  if (qs('input[name="nlu"]')?.checked)          fd.set('nlu', '1');
+
+  const btn = document.getElementById('saveAiBtn');
+  if (btn) { btn.textContent = 'Guardando...'; btn.disabled = true; }
+  fetch('/admin/bot-config/save-ai', { method: 'POST', body: fd })
+    .then(r => r.json())
+    .then(d => {
+      if (btn) { btn.textContent = '💾 Guardar IA'; btn.disabled = false; }
+      if (d.ok) { btn.textContent = '✅ Guardado'; setTimeout(() => { btn.textContent = '💾 Guardar IA'; }, 2000); }
+      else alert('❌ Error al guardar: ' + JSON.stringify(d));
+    })
+    .catch(e => {
+      if (btn) { btn.textContent = '💾 Guardar IA'; btn.disabled = false; }
+      alert('❌ Error de red: ' + e.message);
+    });
+}
+
 function switchTab(tab, btn) {
   document.querySelectorAll('.tab-content').forEach(t => t.classList.remove('active'));
   document.querySelectorAll('.tab-btn').forEach(t => t.classList.remove('active'));

public/index.php

@@ -587,6 +587,53 @@ $routes = [
         exit;
     })()],
 
+    // ─── Admin: guardar solo campos IA (endpoint separado) ───────────────────
+    ['POST', '/admin/bot-config/save-ai', fn() => (function () {
+        SessionAuth::require();
+        header('Content-Type: application/json; charset=utf-8');
+        $companyId = (int)($_POST['company_id'] ?? 0);
+        if ($companyId === 0) { echo json_encode(['ok' => false, 'error' => 'missing company_id']); exit; }
+
+        $company = CompanyRepository::findById($companyId);
+        if (!$company) { echo json_encode(['ok' => false, 'error' => 'not found']); exit; }
+
+        $config = json_decode($company['config_json'] ?? '{}', true) ?: [];
+
+        $aiProvider = trim($_POST['ai_provider'] ?? '');
+        if ($aiProvider !== '') $config['ai_provider'] = $aiProvider; else unset($config['ai_provider']);
+
+        $aiModel = trim($_POST['ai_model'] ?? '');
+        if ($aiModel !== '') $config['ai_model'] = $aiModel;
+
+        $aiTemp = trim($_POST['ai_temperature'] ?? '');
+        if ($aiTemp !== '') $config['ai_temperature'] = (float)$aiTemp;
+
+        $aiPrompt = trim($_POST['ai_prompt'] ?? '');
+        $config['ai_prompt'] = $aiPrompt;
+
+        $config['ai_for_media'] = isset($_POST['ai_for_media']);
+        $config['nlu']          = isset($_POST['nlu']);
+
+        $openaiKey = trim($_POST['openai_api_key'] ?? '');
+        if ($openaiKey !== '') $config['openai_api_key'] = $openaiKey;
+
+        $geminiKey = trim($_POST['gemini_api_key'] ?? '');
+        if ($geminiKey !== '') $config['gemini_api_key'] = $geminiKey;
+
+        $geminiModel = trim($_POST['gemini_model'] ?? '');
+        if ($geminiModel !== '') $config['gemini_model'] = $geminiModel;
+
+        $claudeKey = trim($_POST['claude_api_key'] ?? '');
+        if ($claudeKey !== '') $config['claude_api_key'] = $claudeKey;
+
+        $claudeModel = trim($_POST['claude_model'] ?? '');
+        if ($claudeModel !== '') $config['claude_model'] = $claudeModel;
+
+        CompanyRepository::save(['id' => $companyId, 'config_json' => json_encode($config, JSON_UNESCAPED_UNICODE)]);
+        echo json_encode(['ok' => true]);
+        exit;
+    })()],
+
     // ─── Admin: guardar per_type por categoría (endpoint separado) ───────────
     ['POST', '/admin/bot-config/save-per-type', fn() => (function () {
         SessionAuth::require();