build: switch to Alpine base image and simplify Dockerfile

- Use php:8.4-fpm-alpine for smaller image size
- Replace apt-get with apk package manager
- Use docker-php-ext-install instead of external extension installer
- Remove unnecessary comments and clean up cache appropriately

Dockerfile

@@ -1,31 +1,27 @@
-FROM php:8.4-fpm
+FROM php:8.4-fpm-alpine
 
-# Set working directory early to avoid conflicts with host files
 WORKDIR /var/www
 
 # Install system dependencies
-RUN apt-get update && apt-get install -y \
+RUN apk add --no-cache \
     git \
     curl \
     libpng-dev \
-    libonig-dev \
+    oniguruma-dev \
     libxml2-dev \
     zip \
     unzip \
     libzip-dev \
-    libicu-dev
+    icu-dev
 
-# Install PHP extensions installer
-ADD https://github.com/mlocati/docker-php-extension-installer/releases/latest/download/install-php-extensions /usr/local/bin/
-
-RUN chmod +x /usr/local/bin/install-php-extensions && \
-    install-php-extensions pdo_mysql mbstring exif pcntl bcmath gd zip intl
+# Install PHP extensions
+RUN docker-php-ext-install pdo_mysql mbstring exif pcntl bcmath gd zip intl
 
 # Clear cache
-RUN apt-get clean && rm -rf /var/lib/apt/lists/*
+RUN rm -rf /var/cache/apk/*
 
 # Get latest Composer
-COPY --from=docker.io/library/composer:latest /usr/bin/composer /usr/bin/composer
+COPY --from=composer:latest /usr/bin/composer /usr/bin/composer
 
 # Copy application files and fix permissions
 COPY . /var/www
@@ -34,10 +30,8 @@ RUN chown -R www-data:www-data /var/www && \
     find /var/www -type f -exec chmod 644 {} + && \
     rm -rf /var/www/.circleci /var/www/.github
 
-# Change current user to www
 USER www-data
 
-# Expose port 8000
 EXPOSE 8000
 
 CMD ["php", "artisan", "serve", "--host=0.0.0.0", "--port=8000"]