Send the chosen company when switching branch

app/setting/api/engine/switch_branch.php

@@ -3,7 +3,11 @@
  * switch_branch.php — Switch the active company for the current session.
  *
  * action: 'read'   → return list of companies the user belongs to
- * action: 'update' → switch to the requested company_id
+ * action: 'update' → switch to target_company_id
+ *
+ * The target is read from target_company_id, not company_id: every request
+ * carries company_id = the CURRENT company (prepare_form_data in custom.js),
+ * so reading it made a switch silently re-select the company already active.
  */
 session_start();
 require_once '../../../assets/utils/db_auth.php';
@@ -20,7 +24,7 @@ if ($action === 'read') {
 }
 
 if ($action === 'update') {
-    $target_company_id = (int)($data['company_id'] ?? 0);
+    $target_company_id = (int)($data['target_company_id'] ?? 0);
 
     if (!$target_company_id) {
         $answer['message'] = 'Invalid company.';