Update paths for config/ directory structure

Adjusted all references to match new config/ structure:
- docker/config/nginx/default.conf → config/nginx/default.conf
- docker/init.sql → config/docker/init.sql
- docker/start.sh → config/docker/start.sh

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

New structure consolidates all configuration files under config/
for better organization and clarity.

Tested and verified all services running correctly.

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

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

config/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;