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/001_create_tables.sql

@@ -0,0 +1,46 @@
+-- Create books table
+CREATE TABLE IF NOT EXISTS books (
+    book_code UUID PRIMARY KEY DEFAULT gen_random_uuid(),
+    book_name VARCHAR(200) NOT NULL,
+    cost DECIMAL(10,2) NOT NULL,
+    price DECIMAL(10,2) NOT NULL,
+    discount DECIMAL(10,2) DEFAULT 0,
+    quantity INTEGER NOT NULL,
+    publisher_author VARCHAR(200) NOT NULL,
+    category VARCHAR(100) NOT NULL,
+    description TEXT,
+    image_url TEXT NOT NULL,
+    slug VARCHAR(255) NOT NULL,
+    created_at TIMESTAMP DEFAULT NOW(),
+    updated_at TIMESTAMP DEFAULT NOW()
+);
+
+-- Create indexes for books table
+CREATE INDEX IF NOT EXISTS idx_books_created_at ON books(created_at DESC);
+CREATE INDEX IF NOT EXISTS idx_books_category ON books(category);
+CREATE INDEX IF NOT EXISTS idx_books_slug ON books(slug);
+
+-- Create stationery table
+CREATE TABLE IF NOT EXISTS stationery (
+    stationery_code UUID PRIMARY KEY DEFAULT gen_random_uuid(),
+    stationery_name VARCHAR(200) NOT NULL,
+    cost DECIMAL(10,2) NOT NULL,
+    price DECIMAL(10,2) NOT NULL,
+    discount DECIMAL(10,2) DEFAULT 0,
+    quantity INTEGER NOT NULL,
+    color VARCHAR(100),
+    material VARCHAR(100),
+    dimensions VARCHAR(100),
+    category VARCHAR(100) NOT NULL,
+    description TEXT,
+    image_url TEXT NOT NULL,
+    slug VARCHAR(255) NOT NULL,
+    created_at TIMESTAMP DEFAULT NOW(),
+    updated_at TIMESTAMP DEFAULT NOW()
+);
+
+-- Create indexes for stationery table
+CREATE INDEX IF NOT EXISTS idx_stationery_created_at ON stationery(created_at DESC);
+CREATE INDEX IF NOT EXISTS idx_stationery_category ON stationery(category);
+CREATE INDEX IF NOT EXISTS idx_stationery_slug ON stationery(slug);
+