feat(backend)!: update env variables

[golobitch]

Changes proposed in this pull request

• Change default env variables values
• Rename one environment variable
• Update localenv
• Update integration tests
• Update documentation

Context

fixes #2684

Checklist

• [x] Related issues linked using fixes #number
• [ ] Tests added/updated
• [ ] Documentation added
• [ ] Make sure that all checks pass
• [ ] Bruno collection updated

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