feat: custom labels toggle and inline editing in product list

Adds session-based show/hide toggle for custom labels in admin product list, inline editable fields for custom_label_0..4, and label suggestions with custom entry support. Includes repository/controller updates, UI fixes, tests, and PAUL docs release updates.

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

autoload/Domain/Product/ProductRepository.php

@@ -2205,6 +2205,44 @@ class ProductRepository
         ] );
     }
 
+    /**
+     * Pobiera nazwy etykiet custom_label_0..4 z bazy ustawien.
+     *
+     * @return array<string, string>
+     */
+    public function customLabelNames(): array
+    {
+        $names = [];
+        for ( $index = 0; $index < 5; $index++ ) {
+            $fieldName = 'custom_label_' . $index;
+            $names[$fieldName] = 'Custom label ' . $index;
+        }
+
+        $settingsKeys = [];
+        for ( $index = 0; $index < 5; $index++ ) {
+            $settingsKeys[] = 'custom_label_' . $index . '_name';
+            $settingsKeys[] = 'google_custom_label_' . $index . '_name';
+        }
+
+        $settingsRows = $this->db->select( 'pp_settings', [ 'param', 'value' ], [ 'param' => $settingsKeys ] );
+        if ( is_array( $settingsRows ) ) {
+            foreach ( $settingsRows as $settingRow ) {
+                $param = (string) ( $settingRow['param'] ?? '' );
+                $value = trim( (string) ( $settingRow['value'] ?? '' ) );
+
+                if ( $value === '' ) {
+                    continue;
+                }
+
+                if ( preg_match( '/^(?:google_)?custom_label_([0-4])_name$/', $param, $match ) ) {
+                    $names[ 'custom_label_' . $match[1] ] = $value;
+                }
+            }
+        }
+
+        return $names;
+    }
+
     /**
      * Pobiera sugestie custom label.
      */