feat: Complete onboarding system with No Website functionality

- Add No Website button to Step 2 with business description form
- Implement onboarding cache service for browser-side data storage
- Add business info database models and API endpoints
- Update API key manager to save keys to .env file immediately
- Add database migration scripts for business info table
- Create reset onboarding script for fresh starts
- Implement hybrid data storage (API keys to backend, other data to cache)
- Add comprehensive business info CRUD operations
- Include database table creation and migration tools

backend/database/migrations/add_business_info_table.sql

@@ -0,0 +1,27 @@
+-- Migration: Add user_business_info table
+-- Description: Creates table for storing business information when users don't have websites
+-- Date: 2024-01-XX
+
+CREATE TABLE IF NOT EXISTS user_business_info (
+    id INTEGER PRIMARY KEY AUTOINCREMENT,
+    user_id INTEGER,
+    business_description TEXT NOT NULL,
+    industry VARCHAR(100),
+    target_audience TEXT,
+    business_goals TEXT,
+    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+    updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
+);
+
+-- Create index for faster user lookups
+CREATE INDEX IF NOT EXISTS idx_user_business_info_user_id ON user_business_info(user_id);
+
+-- Add trigger to automatically update updated_at timestamp
+CREATE TRIGGER IF NOT EXISTS update_user_business_info_timestamp 
+    AFTER UPDATE ON user_business_info
+    FOR EACH ROW
+BEGIN
+    UPDATE user_business_info 
+    SET updated_at = CURRENT_TIMESTAMP 
+    WHERE id = NEW.id;
+END;