fix: add max port range validation to prevent DoS scans

[Midoriya-w]

📌 Overview

Added validation limits for port ranges to prevent excessively large scans that could cause resource exhaustion and denial of service.

🛠 Type of Change

• Backend
• Security Fix

✨ Changes Made

• Added maximum allowed port range validation
• Prevented scans like 1-65535 from being accepted
• Added configurable limit using settings.max_port_range_size
• Improved validation error handling
• Reduced risk of CPU and network resource exhaustion

🔗 Related Issue

Closes #308

[utksh1]

Closing as invalid/low-quality. This duplicates #316/#317 work, is already conflicting, introduces a typo in config.py (manFagement), repeats comments, and changes valid port-range tests to fit the new limit instead of proving the limit safely. Labeled gssoc:invalid and gssoc:ai-slop.

[Midoriya-w]

Understood @utksh1 . Thanks for the feedback. I’ll keep future PRs smaller, avoid bundling unrelated changes, and ensure all commands/examples are repo-supported before submitting again.