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/operations/deployment.md

@@ -0,0 +1,46 @@
+# Deployment
+
+CLICD can run directly on the host or behind a reverse proxy. In production, set up access control before exposing it to administrators.
+
+## Service Exposure
+
+The default web port is `8999`:
+
+```text
+http://YOUR_SERVER_IP:8999
+```
+
+Recommendations:
+
+- Allow only fixed administrator IPs.
+- Use a reverse proxy with HTTPS.
+- Do not expose the real login URL in public docs or screenshots.
+
+## systemd
+
+Common commands:
+
+```bash
+systemctl status clicd
+systemctl restart clicd
+systemctl enable clicd
+journalctl -u clicd -f
+```
+
+## Firewall
+
+At minimum, confirm:
+
+- The panel port is open only to trusted sources.
+- NAT mapped ports are opened only as needed.
+- The SSH management port does not conflict with container mappings.
+- IPv6 firewall rules are planned together with IPv4 rules.
+
+## Backups
+
+Back up regularly:
+
+- CLICD configuration directory.
+- SQLite database.
+- Container configuration.
+- Snapshots or external data backups for important containers.