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/Tasks.tsx

@@ -2,6 +2,7 @@ import React, { useState, useMemo } from 'react';
 import { useTranslation } from 'react-i18next';
 import { useQuery, useMutation, useQueryClient } from '@tanstack/react-query';
 import axios from '../api/client';
+import HelpButton from '../components/HelpButton';
 import {
   Plus,
   Play,
@@ -258,13 +259,16 @@ const Tasks: React.FC = () => {
     <div className="p-6 max-w-7xl mx-auto">
       {/* Header */}
       <div className="flex items-center justify-between mb-6">
-        <div>
-          <h1 className="text-3xl font-bold text-gray-900 dark:text-white">
-            {t('Tasks')}
-          </h1>
-          <p className="text-gray-600 dark:text-gray-400 mt-1">
-            Schedule and manage automated plugin executions
-          </p>
+        <div className="flex items-start gap-4">
+          <div>
+            <h1 className="text-3xl font-bold text-gray-900 dark:text-white">
+              {t('Tasks')}
+            </h1>
+            <p className="text-gray-600 dark:text-gray-400 mt-1">
+              Schedule and manage automated plugin executions
+            </p>
+          </div>
+          <HelpButton helpPath="/help/tasks" />
         </div>
         <button
           onClick={() => setShowCreateModal(true)}