Bug: ThemeContext missing Provider wrapper in hooks.md

Description

In pages/hooks.md, the ThemeContext example shows context creation and consumption but is missing the ThemeProvider component that should wrap children with the context value.

Location

File: pages/hooks.md
Lines: 617-626

Current Code

import { createContext, use } from 'react'

const ThemeContext = createContext()

const ThemeConsumer = () => {
  const { theme, toggleTheme } = use(ThemeContext)

  return <button onClick={toggleTheme}>Current theme: {theme}</button>
}

Expected Code

import { createContext, use, useState } from 'react'

const ThemeContext = createContext()

const ThemeProvider = ({ children }) => {
  const [theme, setTheme] = useState('light')

  const toggleTheme = () => {
    setTheme(prev => prev === 'light' ? 'dark' : 'light')
  }

  return (
    <ThemeContext.Provider value={{ theme, toggleTheme }}>
      {children}
    </ThemeContext.Provider>
  )
}

const ThemeConsumer = () => {
  const { theme, toggleTheme } = use(ThemeContext)

  return <button onClick={toggleTheme}>Current theme: {theme}</button>
}

// Usage
function App() {
  return (
    <ThemeProvider>
      <ThemeConsumer />
    </ThemeProvider>
  )
}

Why This Matters

• Without a Provider, calling use(ThemeContext) will return undefined and cause runtime errors
• This is teaching material - students need to see the complete pattern of Context creation, Provider, and Consumer
• The Provider pattern with children props is a fundamental React concept that should be demonstrated

References

• React createContext Docs
• React use Hook Docs

Start in pages/hooks.md at lines 617-626 and compare the ThemeContext example with the referenced React createContext and use documentation. Complete the example with the ThemeProvider and usage shown in the issue, then verify that the teaching example provides a context value and supports toggling the theme.