Add comprehensive documentation for CLICD features and operations

- Introduced Container Management documentation covering lifecycle operations, resource management, and console access.
- Added Dashboard documentation detailing metrics and related APIs.
- Created Host Report documentation summarizing host environment and resource status.
- Included Image Management documentation for template handling and management actions.
- Documented Networking and Routing features including NAT4 and IPv6 management.
- Added Security Alerts documentation outlining alert scenarios and API usage.
- Created Snapshot Management documentation for snapshot operations and scheduling.
- Documented Sub-user management for granting access to specific containers.
- Added Configuration guide detailing runtime settings and security recommendations.
- Created Installation guide for setting up CLICD with requirements and steps.
- Added Introduction and Quick Start guides for new users.
- Documented Upgrade process with version checking and pre-upgrade checklist.
- Created Deployment guide for service exposure and firewall recommendations.
- Added FAQ section addressing common questions and concerns.
- Documented Troubleshooting steps for common issues encountered.

docs/en/features/security.md

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+# Security Alerts
+
+CLICD includes lightweight security alerts based on connection behavior. It does not keep full normal connection logs; it focuses on abnormal behavior and high-risk patterns.
+
+## Covered Scenarios
+
+- Port scanning.
+- Lateral scanning.
+- Brute-force tendencies.
+- SMTP abuse.
+- UDP reflection risk.
+- Suspicious ports related to mining, proxies, VPNs, Tor, and similar services.
+
+## APIs
+
+```http
+GET /api/v1/security/alerts
+POST /api/v1/security/check
+GET /api/v1/security/logs?container={name}
+GET /api/v1/security/summary
+GET /api/v1/security/settings
+PUT /api/v1/security/settings
+```
+
+## Automatic Shutdown
+
+Security settings can enable automatic shutdown after alerts. Before enabling it, observe for a while and make sure the rules do not affect normal services.
+
+## Logging Advice
+
+Security alerts are risk signals. They should not replace a professional firewall, intrusion detection, or centralized logging system. For public services, still combine them with security groups, firewall rules, Fail2ban, and similar tools.