docs(readme): add user deployment guide

[bao-cn]

Summary

Add a user-facing deployment guide to both README files.

Motivation

The existing documentation focused on contributors and technical details. Non-developers need a short, direct path to run Terminal Blog manually or with Docker.

Implementation

• Add a dedicated User Deployment section in Chinese and English.
• Document manual deployment on Windows, Linux, and macOS.
• Document Docker Desktop / Docker Engine setup, .env configuration, lifecycle commands, updates, and persistent volumes.
• Keep the developer Quick Start section separate from the user workflow.

Behavior and compatibility

Documentation-only change. No runtime, API, configuration, or data-format changes.

Risk

No application risk. The guide explicitly warns against the default root password and destructive docker compose down -v.

Verification

• npx prettier --check README.md README.en.md
• git diff --check
• Checked that Dockerfile, compose.yaml, and config/site.config.json exist.

Screenshots or recordings

Not applicable; this pull request changes documentation only.

Checklist

• I read and followed CONTRIBUTING.md.
• The change is focused and contains only README updates.
• I updated README and deployment guidance where necessary.
• Full application test suite was not run because this is documentation-only.