Update Polish translations and enhance checkout styles

- Changed the button text for adding a voucher code to Polish ("Dodaj kod rabatowy").
- Updated placeholder text in checkout form fields to use field labels.
- Modified shipping template to display shipping time in Polish.
- Refined CSS styles for better layout and responsiveness in checkout areas.
- Updated custom CSS version in the head template and added a script to move the free shipping message to the top of the container.

modules/thecheckout/views/templates/front/_partials/checkout-form-fields.tpl

@@ -240,7 +240,7 @@
             name="{$field.name|escape:'javascript':'UTF-8'}"
             type="{$field.type|escape:'javascript':'UTF-8'}"
             value="{$field.value|escape:'htmlall':'UTF-8'}"
-            placeholder="{$placeholder|escape:'javascript':'UTF-8'}"
+            placeholder=" {$field.label|escape:'htmlall':'UTF-8'}"
             {if $field.autoCompleteAttribute}autocomplete="{$field.autoCompleteAttribute|escape:'javascript':'UTF-8'}"{/if}
             {if $field.maxLength}maxlength="{$field.maxLength|escape:'javascript':'UTF-8'}"{/if}
             {if $field.required}required{/if}
@@ -257,11 +257,11 @@
       <span class="effects-helper"></span>
 
 
-      {if $field.type !== 'checkbox' && $field.type !== 'radio-buttons' && $field.type !== 'birthday'}
+      {* {if $field.type !== 'checkbox' && $field.type !== 'radio-buttons' && $field.type !== 'birthday'}
         <span class="field-label"{if !$field.required} data-optional-label="{l s='(optional)' mod='thecheckout'}"{/if}>
           {$field.label|escape:'htmlall':'UTF-8'}
         </span>
-      {/if}
+      {/if} *}
 
 
     </label>