Rename plugins feature to automations throughout codebase

- Update billing catalog feature codes: can_use_plugins → can_use_automations, can_create_plugins → can_create_automations
- Update all backend permission checks to use new feature codes
- Update API views to return automations permissions to frontend
- Update frontend types and hooks to use automations terminology
- Move Tasks to Extend section in Sidebar alongside Automations
- Update all related tests

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

frontend/src/components/Sidebar.tsx

@@ -138,16 +138,6 @@ const Sidebar: React.FC<SidebarProps> = ({ business, user, isCollapsed, toggleCo
               isCollapsed={isCollapsed}
             />
           )}
-          {hasPermission('can_access_tasks') && (
-            <SidebarItem
-              to="/dashboard/tasks"
-              icon={Clock}
-              label={t('nav.tasks', 'Tasks')}
-              isCollapsed={isCollapsed}
-              locked={!canUse('automations') || !canUse('tasks')}
-              badgeElement={<UnfinishedBadge />}
-            />
-          )}
           {(isStaff && hasPermission('can_access_my_schedule')) && (
             <SidebarItem
               to="/dashboard/my-schedule"
@@ -293,17 +283,29 @@ const Sidebar: React.FC<SidebarProps> = ({ business, user, isCollapsed, toggleCo
           </SidebarSection>
         )}
 
-        {/* Extend Section - Automations */}
-        {hasPermission('can_access_automations') && (
+        {/* Extend Section - Tasks & Automations */}
+        {(hasPermission('can_access_tasks') || hasPermission('can_access_automations')) && (
           <SidebarSection title={t('nav.sections.extend', 'Extend')} isCollapsed={isCollapsed}>
-            <SidebarItem
-              to="/dashboard/automations/my-automations"
-              icon={Plug}
-              label={t('nav.automations', 'Automations')}
-              isCollapsed={isCollapsed}
-              locked={!canUse('automations')}
-              badgeElement={<UnfinishedBadge />}
-            />
+            {hasPermission('can_access_tasks') && (
+              <SidebarItem
+                to="/dashboard/tasks"
+                icon={Clock}
+                label={t('nav.tasks', 'Tasks')}
+                isCollapsed={isCollapsed}
+                locked={!canUse('automations') || !canUse('tasks')}
+                badgeElement={<UnfinishedBadge />}
+              />
+            )}
+            {hasPermission('can_access_automations') && (
+              <SidebarItem
+                to="/dashboard/automations/my-automations"
+                icon={Plug}
+                label={t('nav.automations', 'Automations')}
+                isCollapsed={isCollapsed}
+                locked={!canUse('automations')}
+                badgeElement={<UnfinishedBadge />}
+              />
+            )}
           </SidebarSection>
         )}