feat: Dashboard redesign, plan permissions, and help docs improvements

Major updates including:
- Customizable dashboard with drag-and-drop widget grid layout
- Plan-based feature locking for plugins and tasks
- Comprehensive help documentation updates across all pages
- Plugin seeding in deployment process for all tenants
- Permission synchronization system for subscription plans
- QuotaOverageModal component and enhanced UX flows

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

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

frontend/src/hooks/usePlanFeatures.ts

@@ -84,6 +84,7 @@ export const FEATURE_NAMES: Record<FeatureKey, string> = {
   white_label: 'White Label',
   custom_oauth: 'Custom OAuth',
   plugins: 'Custom Plugins',
+  tasks: 'Scheduled Tasks',
   export_data: 'Data Export',
   video_conferencing: 'Video Conferencing',
   two_factor_auth: 'Two-Factor Authentication',
@@ -103,6 +104,7 @@ export const FEATURE_DESCRIPTIONS: Record<FeatureKey, string> = {
   white_label: 'Remove SmoothSchedule branding and use your own',
   custom_oauth: 'Configure your own OAuth credentials for social login',
   plugins: 'Create custom plugins to extend functionality',
+  tasks: 'Create scheduled tasks to automate plugin execution',
   export_data: 'Export your data to CSV or other formats',
   video_conferencing: 'Add video conferencing links to appointments',
   two_factor_auth: 'Require two-factor authentication for enhanced security',