Always send reasoning parameters in Responses requests (#32206)

## What changed

- Build a reasoning payload for every Responses request and always include `reasoning.encrypted_content`.
- Remove `supports_reasoning_summaries` from model metadata and retire the `model_supports_reasoning_summaries` configuration override.
- Use configured or model-default reasoning effort without a capability gate, including for guardian reviews and tracing.

GitOrigin-RevId: 2c9f194a5d2d4d688a2235299e6358f82ab8e1ea

codex-rs/core/src/client_tests.rs

@@ -262,7 +262,6 @@ fn test_model_info() -> ModelInfo {
         "upgrade": null,
         "base_instructions": "base instructions",
         "model_messages": null,
-        "supports_reasoning_summaries": false,
         "support_verbosity": false,
         "default_verbosity": null,
         "apply_patch_tool_type": null,