docs: add Agent Runtime deployment guide

[HynLcc]

Summary

• add bilingual self-hosted Agent Runtime Docker deployment guides
• add the guides to the Self-hosted production deployment navigation
• link the AI Settings and Sandbox Agent pages to the deployment guide
• document early-stage availability, the current OpenSandbox/Teable Infra path, the support channel, and Teable connection variables

Validation

• git diff --check
• mintlify validate