Migrate data storage from Couchbase to Redis

Replaces Couchbase with Redis for data persistence, updating environment variables, Docker Compose files, and repository logic. Removes Couchbase and Jackson dependencies, introduces Gson for JSON serialization, and refactors models and repositories to support Redis. Adds utility classes for Redis and Gson, and updates tests and scrapers to use Gson.

.env.example

@@ -1,11 +1,8 @@
 # Copy this file to .env and customize the values for your environment
 # cp .env.example .env
 
-# Couchbase configuration
-COUCHBASE_CONNECTION_STRING=couchbase://localhost
-COUCHBASE_USERNAME=admin
-COUCHBASE_PASSWORD=your_password_here
-COUCHBASE_BUCKET_NAME=store_scraper
+# Redis configuration
+REDIS_URL=localhost:6379
 
 # Telegram Bot configuration
 TELEGRAM_BOT_TOKEN=your_telegram_bot_token_here