Ahmed Ibrahim ddcc60a085 Update defaults to gpt-5.1 (#6652) ...

## Summary
- update documentation, example configs, and automation defaults to
reference gpt-5.1 / gpt-5.1-codex
- bump the CLI and core configuration defaults, model presets, and error
messaging to the new models while keeping the model-family/tool coverage
for legacy slugs
- refresh tests, fixtures, and TUI snapshots so they expect the upgraded
defaults

## Testing
- `cargo test -p codex-core
config::tests::test_precedence_fixture_with_gpt5_profile`


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[Codex
Task](https://chatgpt.com/codex/tasks/task_i_6916c5b3c2b08321ace04ee38604fc6b)

2025-11-17 17:40:11 -08:00

..

config.toml

Update defaults to gpt-5.1 (#6652)

2025-11-17 17:40:11 -08:00