revert(ui): move Doctor trigger back to the page toolbar

Undo the Doctor relocation from fe160134 while keeping that commit's
unrelated header changes (full-width header, 32px click targets,
role/tabindex plus Enter/Space activation).

- Restore the .doctor-control-group button in controls.html
- Drop the .doctor-toggle icon and the hamburger menu entry from the header
- Remove the Header.js 'doctor' dropdown action forwarding to the button
- Drop the header-scoped doctor-toggle styles
- Restore the .doctor-trigger styles (desktop and mobile) in doctor-modal.css

templates/components/controls.html

@@ -144,6 +144,13 @@
                 </button>
             </div>
             {% endif %}
+            <div class="control-group doctor-control-group">
+                <button id="doctorTriggerBtn" class="doctor-trigger" title="{{ t('doctor.buttonTitle', default='Run diagnostics and common fixes') }}">
+                    <i class="fas fa-stethoscope"></i>
+                    <span>{{ t('doctor.title', default='Doctor') }}</span>
+                    <span id="doctorStatusBadge" class="doctor-status-badge hidden" aria-hidden="true"></span>
+                </button>
+            </div>
         </div>
     </div>
 </div>