Add initial project structure with core functionality for book and stationery uploads

- Created main application entry point in `main.go`.
- Added configuration management in `config/config.go` and tests in `config/config_test.go`.
- Implemented handlers for book and stationery uploads in `handlers/book.go` and `handlers/stationery.go`, including validation logic.
- Established database connection and services in `services/database.go` and `services/book_service.go`.
- Defined models for books and stationery in `models/book.go` and `models/stationery.go`.
- Set up Firebase integration for image uploads in `services/firebase.go`.
- Created migration scripts for database schema in `migrations/001_create_tables.sql` and subsequent updates.
- Added CORS and error handling middleware.
- Included comprehensive tests for handlers, services, and utilities.
- Documented API endpoints and usage in `README.md` and migration instructions in `migrations/README.md`.
- Introduced `.gitignore` to exclude unnecessary files and directories.
- Added Go module support with `go.mod` and `go.sum` files.
- Implemented utility functions for slug generation and validation in `utils/slug.go` and `utils/validation.go`.

migrations/README.md

@@ -0,0 +1,41 @@
+# Database Migrations
+
+## Running Migrations
+
+### Prerequisites
+1. Ensure PostgreSQL is running
+2. Create the database if it doesn't exist:
+   ```bash
+   psql -U postgres -c "CREATE DATABASE jd_book_uploader;"
+   ```
+3. Ensure your `.env` or `.env.local` file in the backend directory has the correct database credentials
+
+### Run Migration
+
+```bash
+cd backend
+./scripts/run_migration.sh
+```
+
+Or manually:
+```bash
+cd backend
+export $(grep -v '^#' .env.local | grep -v '^$' | xargs)
+PGPASSWORD="$DB_PASSWORD" psql -h "$DB_HOST" -p "$DB_PORT" -U "$DB_USER" -d "$DB_NAME" -f migrations/001_create_tables.sql
+```
+
+### Verify Schema
+
+```bash
+cd backend
+./scripts/verify_schema.sh
+```
+
+This will show:
+- Table structures for `books` and `stationery`
+- All indexes created on both tables
+
+## Migration Files
+
+- `001_create_tables.sql` - Creates books and stationery tables with indexes
+