feat: Migrate data storage to PostgreSQL with schema setup, initialization script, and update documentation

README.md

@@ -176,13 +176,35 @@ Example configuration for Claude Desktop (`claude_desktop_config.json`):
 
 ## Data Storage
 
-All data is stored locally in JSON files in the `data/` directory:
-- `codeSnippets.json` - Code snippets
-- `notes.json` - Personal notes
-- `tasks.json` - Tasks
-- `babyMilestones.json` - Baby milestones
-- `mathResources.json` - Math resources
-- `gameWishlist.json` - Game wishlist
+All data is stored in PostgreSQL database. The application requires a PostgreSQL database connection.
+
+### Database Setup
+
+1. **Configure Database Connection**
+
+   Set the `DATABASE_URL` environment variable in your `.env` file:
+   ```
+   DATABASE_URL=postgresql://user:password@host:port/database
+   ```
+
+2. **Initialize Database Schema**
+
+   Run the initialization script to create all required tables:
+   ```bash
+   bun run init-db
+   ```
+
+   This will create the following tables:
+   - `code_snippets` - Code snippets
+   - `notes` - Personal notes
+   - `tasks` - Tasks
+   - `baby_milestones` - Baby milestones
+   - `math_resources` - Math resources
+   - `game_wishlist` - Game wishlist
+
+### Database Schema
+
+The database schema is defined in `src/storage/schema.sql`. All tables include appropriate indexes for optimal query performance.
 
 ## Development