Remove duplicate getAccountMappings() method declaration

Fixed:
- Removed old getAccountMappings() method on line 615
- Kept the new version that joins with chart of accounts
- This fixes the 'Cannot redeclare' PHP Fatal error

The new method properly retrieves account labels from Dolibarr's accounting_account table.

core/class/declarationtva.class.php

@@ -607,35 +607,6 @@ class DeclarationTVA
         return $result !== false;
     }
 
-    /**
-     * Get account mappings
-     *
-     * @return array Account mappings
-     */
-    public function getAccountMappings()
-    {
-        $sql = "SELECT ca3_line, account_code, account_label, vat_rate 
-                FROM " . MAIN_DB_PREFIX . "declarationtva_account_mappings 
-                WHERE entity = " . $this->entity . " AND is_active = 1 
-                ORDER BY ca3_line";
-
-        $result = $this->db->query($sql);
-        $mappings = array();
-
-        if ($result) {
-            while ($obj = $this->db->fetch_object($result)) {
-                $mappings[] = array(
-                    'ca3_line' => $obj->ca3_line,
-                    'account_code' => $obj->account_code,
-                    'account_label' => $obj->account_label,
-                    'vat_rate' => $obj->vat_rate
-                );
-            }
-        }
-
-        return $mappings;
-    }
-
     /**
      * Get period information
      *