create-environment-variables

Guide for creating and naming environment variables in this project. All project environment variables must use the TORRUST_TD_ prefix. Covers the condition-based vs action-based naming decision framework, when to use each approach, and practical examples. Use when adding new environment variables, changing existing env var names, or deciding how to name a toggle or flag. Triggers on "environment variable", "env var", "TORRUST_TD_", "variable naming", "feature flag", "feature toggle", "configuration flag", or "add env var".