feat: Add comprehensive help documentation system and plugin creation page

- Add CreatePlugin.tsx page for custom plugin creation with code editor
- Add HelpButton component for contextual help links
- Create 21 new help pages covering all dashboard features:
  - Core: Dashboard, Scheduler, Tasks
  - Manage: Customers, Services, Resources, Staff
  - Communicate: Messages (Ticketing already existed)
  - Money: Payments
  - Extend: Plugins overview and creation guide
  - Settings: General, Resource Types, Booking, Appearance, Email, Domains, API, Auth, Billing, Quota
- Update HelpGuide.tsx as main documentation hub with quick start guide
- Add routes for all help pages in App.tsx
- Add HelpButton to Dashboard, Customers, Services, and Tasks pages

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

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

frontend/src/pages/Customers.tsx

@@ -16,6 +16,7 @@ import {
   Eye
 } from 'lucide-react';
 import Portal from '../components/Portal';
+import HelpButton from '../components/HelpButton';
 
 interface CustomersProps {
   onMasquerade: (user: User) => void;
@@ -125,9 +126,12 @@ const Customers: React.FC<CustomersProps> = ({ onMasquerade, effectiveUser }) =>
   return (
     <div className="p-8 max-w-7xl mx-auto space-y-6">
       <div className="flex flex-col sm:flex-row sm:items-center justify-between gap-4">
-        <div>
-          <h2 className="text-2xl font-bold text-gray-900 dark:text-white">{t('customers.title')}</h2>
-          <p className="text-gray-500 dark:text-gray-400">{t('customers.description')}</p>
+        <div className="flex items-start gap-4">
+          <div>
+            <h2 className="text-2xl font-bold text-gray-900 dark:text-white">{t('customers.title')}</h2>
+            <p className="text-gray-500 dark:text-gray-400">{t('customers.description')}</p>
+          </div>
+          <HelpButton helpPath="/help/customers" />
         </div>
         <button
           onClick={() => setIsAddModalOpen(true)}