+ [misc] Add unit tests for programModel::getProductPairsByID() method

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

module/program/test/lib/program.unittest.class.php

@@ -653,4 +653,19 @@ class programTest
 
         return $result;
     }
+
+    /**
+     * Test getProductPairsByID method.
+     *
+     * @param  int $programID
+     * @access public
+     * @return array
+     */
+    public function getProductPairsByIDTest(int $programID): array
+    {
+        $result = $this->program->getProductPairsByID($programID);
+        if(dao::isError()) return dao::getError();
+
+        return $result;
+    }
 }