Reorganize Docker-related files into docker/ directory

Moved Docker infrastructure files to dedicated docker/ folder:
- config/nginx/default.conf → docker/config/nginx/default.conf
- init.sql → docker/init.sql
- start.sh → docker/start.sh (currently unused)

Updated:
- docker-compose.yml: Adjusted volume paths
- README.md: Updated project structure documentation

Benefits:
- Clear separation between infrastructure (docker/) and application (src/)
- Better project organization
- Easier to understand for new developers

Docker Compose and Dockerfile remain in root for convenience.
All services tested and working correctly.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

docker/config/nginx/default.conf

@@ -0,0 +1,31 @@
+server {
+    listen 80;
+    server_name localhost;
+    root /var/www/html;
+    index index.php index.html;
+
+    error_log /var/log/nginx/error.log;
+    access_log /var/log/nginx/access.log;
+
+    location / {
+        try_files $uri $uri/ /index.php?$query_string;
+    }
+
+    location ~ \.php$ {
+        try_files $uri =404;
+        fastcgi_split_path_info ^(.+\.php)(/.+)$;
+        fastcgi_pass localhost:9000;
+        fastcgi_index index.php;
+        include fastcgi_params;
+        fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
+        fastcgi_param PATH_INFO $fastcgi_path_info;
+    }
+
+    location ~ /\.ht {
+        deny all;
+    }
+
+    location ~ /\.git {
+        deny all;
+    }
+}

docker/init.sql

@@ -0,0 +1,66 @@
+-- Database initialization script for Web Crawler
+
+-- Crawl Jobs Table
+CREATE TABLE IF NOT EXISTS crawl_jobs (
+    id INT AUTO_INCREMENT PRIMARY KEY,
+    domain VARCHAR(255) NOT NULL,
+    status ENUM('pending', 'running', 'completed', 'failed') DEFAULT 'pending',
+    total_pages INT DEFAULT 0,
+    total_links INT DEFAULT 0,
+    started_at TIMESTAMP NULL,
+    completed_at TIMESTAMP NULL,
+    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+    INDEX idx_domain (domain),
+    INDEX idx_status (status)
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;
+
+-- Pages Table
+CREATE TABLE IF NOT EXISTS pages (
+    id INT AUTO_INCREMENT PRIMARY KEY,
+    crawl_job_id INT NOT NULL,
+    url VARCHAR(2048) NOT NULL,
+    title VARCHAR(500),
+    status_code INT,
+    content_type VARCHAR(100),
+    crawled_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+    FOREIGN KEY (crawl_job_id) REFERENCES crawl_jobs(id) ON DELETE CASCADE,
+    INDEX idx_crawl_job (crawl_job_id),
+    INDEX idx_url (url(255)),
+    UNIQUE KEY unique_job_url (crawl_job_id, url(255))
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;
+
+-- Links Table
+CREATE TABLE IF NOT EXISTS links (
+    id INT AUTO_INCREMENT PRIMARY KEY,
+    page_id INT NOT NULL,
+    crawl_job_id INT NOT NULL,
+    source_url VARCHAR(2048) NOT NULL,
+    target_url VARCHAR(2048) NOT NULL,
+    link_text VARCHAR(1000),
+    is_nofollow BOOLEAN DEFAULT FALSE,
+    is_internal BOOLEAN DEFAULT TRUE,
+    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+    FOREIGN KEY (page_id) REFERENCES pages(id) ON DELETE CASCADE,
+    FOREIGN KEY (crawl_job_id) REFERENCES crawl_jobs(id) ON DELETE CASCADE,
+    INDEX idx_page (page_id),
+    INDEX idx_crawl_job (crawl_job_id),
+    INDEX idx_source_url (source_url(255)),
+    INDEX idx_target_url (target_url(255)),
+    INDEX idx_nofollow (is_nofollow)
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;
+
+-- Queue Table for parallel processing
+CREATE TABLE IF NOT EXISTS crawl_queue (
+    id INT AUTO_INCREMENT PRIMARY KEY,
+    crawl_job_id INT NOT NULL,
+    url VARCHAR(2048) NOT NULL,
+    depth INT DEFAULT 0,
+    status ENUM('pending', 'processing', 'completed', 'failed') DEFAULT 'pending',
+    retry_count INT DEFAULT 0,
+    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
+    processed_at TIMESTAMP NULL,
+    FOREIGN KEY (crawl_job_id) REFERENCES crawl_jobs(id) ON DELETE CASCADE,
+    INDEX idx_status (status),
+    INDEX idx_crawl_job (crawl_job_id),
+    UNIQUE KEY unique_job_url (crawl_job_id, url(255))
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;

docker/start.sh

@@ -0,0 +1,7 @@
+#!/bin/bash
+
+# Start PHP-FPM
+php-fpm -D
+
+# Start Nginx in foreground
+nginx -g 'daemon off;'