## Summary
- Change `EnvironmentProvider` to return concrete `Environment`
instances instead of `EnvironmentConfigurations`.
- Make `DefaultEnvironmentProvider` provide the provider-visible `local`
environment plus optional `remote` environment from
`CODEX_EXEC_SERVER_URL`.
- Keep `EnvironmentManager` as the concrete cache while exposing its own
explicit local environment for `local_environment()` fallback paths.
## Validation
- `just fmt`
- `git diff --check`
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Co-authored-by: Codex <noreply@openai.com>
starr-openai