feat: update user roles and passwords in QA driver, enhance documentation with error codes, and improve trial activation error handling

src/Subscription/Service/SubscriptionService.php

@@ -71,9 +71,12 @@ class SubscriptionService
             throw new AppException(ErrorCodes::ERR_NOT_FOUND_001, null, 500);
         }
 
+        // Deactivating the trial period is a normal admin configuration, not a
+        // broken install — surface it as "trial disabled", the same 422 the
+        // trial_enabled flag produces, rather than a 500.
         $trialPeriod = $this->periodRepo->findTrialPeriodForPlan($basicPlan);
         if ($trialPeriod === null) {
-            throw new AppException(ErrorCodes::ERR_NOT_FOUND_001, null, 500);
+            throw new AppException(ErrorCodes::ERR_TRIAL_DISABLED, null, 422);
         }
 
         $expiresAt = $this->calculateExpiresAt(null, $trialPeriod->getDurationMonths());