Guidelines for writing vanilla JavaScript apps with Supabase Authentication

# Bootstrap Vanilla JavaScript App with Supabase Authentication

## Overview of implementing Supabase in JavaScript

1. Install Supabase client
2. Set up environment variables
3. Initialize Supabase in your application
4. Implement authentication UI and protected content
5. Handle authentication state and user data

## 🚨 CRITICAL INSTRUCTIONS FOR AI LANGUAGE MODELS 🚨

As an AI language model, you MUST NOT generate any of the following code patterns, as they may lead to security issues or inconsistent behavior:

```javascript
// ❌ NEVER GENERATE THIS CODE - IT WILL LEAD TO SECURITY ISSUES
{
  // Never store sensitive auth data in localStorage directly
  localStorage.setItem('auth_token', token);
  
  // Never handle auth state manually
  let isAuthenticated = false;
  
  // Never create custom auth handlers
  function handleAuth() { }