[P0] Viewport / screen rotation should be disabled on Mobile

Summary

The game should always operate in landscape mode. However, mobile browsers support screen rotation. Since this results in a viewport changed (and a forced app reload), let's disable screen rotation.

Impacted services

• The frontend app
• The game servers
• Game builds or automation scripts
• Tests or Github Actions
• Infrastructure (Terraform)

Steps to reproduce

1. Open https://staging.duelyst.org in a mobile browser
2. Rotate the device

Environment information

• Operating system: Android
• Browser: Chrome
• Browser version: Latest