fix: various inline style cleanup, a11y improvements, and bind_param bug

- Replace style="text-align:center" with .lt-text-center utility class in
  WorkflowDesignerView, CustomFieldsView, error_403, error_404, DashboardView JS string
- Replace style="margin-top:..." with .lt-mt-sm utility in WorkflowDesignerView
- Switch comment-edit-raw data-store textareas to .is-hidden class (TicketView PHP
  + JS-rendered; ticket.js template literal) — these are never shown, only read via .value
- Add aria-describedby="visibilityGroupsHint" + id on hint <p> in CreateTicketView
- Fix bind_param type string bug in manage_workflows.php PUT handler: 'ssiiiii' → 'ssiiii'
  (7 type chars for 6 params caused binding error on workflow transition updates)

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

views/CreateTicketView.php

@@ -185,7 +185,7 @@ include __DIR__ . '/layout_header.php';
         <p id="visibilityHint" class="lt-form-hint">Everyone who is logged in can view this ticket.</p>
       </div>
 
-      <div id="visibilityGroupsContainer" class="lt-form-group is-hidden" aria-live="polite">
+      <div id="visibilityGroupsContainer" class="lt-form-group is-hidden" aria-live="polite" aria-describedby="visibilityGroupsHint">
         <label class="lt-label lt-text-cyan">Allowed Groups</label>
         <div class="visibility-groups-list lt-flex lt-flex-wrap lt-flex-gap-sm">
           <?php
@@ -205,7 +205,7 @@ include __DIR__ . '/layout_header.php';
             <span class="lt-text-muted lt-text-sm">No groups available</span>
           <?php endif ?>
         </div>
-        <p class="lt-form-hint lt-form-hint--warn">Select at least one group for Internal visibility.</p>
+        <p id="visibilityGroupsHint" class="lt-form-hint lt-form-hint--warn">Select at least one group for Internal visibility.</p>
       </div>
     </div>
   </div>