Rename plugins to automations and fix scheduler/payment bugs

Major changes:
- Rename "plugins" to "automations" throughout codebase
- Move automation system to dedicated app (scheduling/automations/)
- Add new automation marketplace, creation, and management pages

Bug fixes:
- Fix payment endpoint 500 errors (use has_feature() instead of attribute)
- Fix scheduler showing "0 AM" instead of "12 AM"
- Fix scheduler business hours double-inversion display issue
- Fix scheduler scroll-to-current-time when switching views
- Fix week view centering on wrong day (use Sunday-based indexing)
- Fix capacity widget overflow with many resources
- Fix Recharts minWidth/minHeight console warnings

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

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

frontend/src/components/marketing/AutomationShowcase.tsx

@@ -4,7 +4,7 @@ import { Mail, Calendar, Bell, ArrowRight, Zap, CheckCircle2, Code, LayoutGrid }
 import { useTranslation } from 'react-i18next';
 import CodeBlock from './CodeBlock';
 
-const PluginShowcase: React.FC = () => {
+const AutomationShowcase: React.FC = () => {
     const { t } = useTranslation();
     const [activeTab, setActiveTab] = useState(0);
     const [viewMode, setViewMode] = useState<'marketplace' | 'code'>('marketplace');
@@ -174,7 +174,7 @@ const PluginShowcase: React.FC = () => {
                                     // Code View
                                     <CodeBlock
                                         code={examples[activeTab].code}
-                                        filename={`${examples[activeTab].id}_plugin.py`}
+                                        filename={`${examples[activeTab].id}_automation.py`}
                                     />
                                 )}
 
@@ -194,4 +194,4 @@ const PluginShowcase: React.FC = () => {
     );
 };
 
-export default PluginShowcase;
+export default AutomationShowcase;