Merge upstream PR #837, preserving its original commits and resolving the UsageModelDisplay layout conflict after #841. Cover response models alongside dynamic service-tier badges in detail tests.
Raw chain-of-thought was written to both `content` (`reasoning_text`) and
`summary` (`summary_text`), and the stream emitter sent the same delta on
`response.reasoning_text.delta` *and* `response.reasoning_summary_text.delta`.
Clients that render both channels therefore printed every thinking chunk
twice — most visibly the Codex CLI, whose thinking panel repeated itself.
OpenAI keeps the two channels distinct: `content` carries the raw CoT while
`summary` is the summarised view. Emit the thinking on `content` only:
- `openai_responses_reasoning_text_fields` becomes
`openai_responses_reasoning_text_parts`, returning just the `content` array;
reasoning items keep `summary: []` (or a provider-supplied summary).
- The Responses stream emitter emits `response.reasoning_text.delta` /
`.done` and no longer mirrors them onto the summary events. The reasoning
`output_item.added` no longer announces a `reasoning_summary_part`.
- The provider-state reasoning reader accepts `content` (`reasoning_text`)
first and falls back to `summary`, so it also understands items produced by
older Aether versions; its state field is renamed accordingly.
- Non-streaming builders (Chat -> Responses, manual Responses response, Grok
gateway) place the thinking on `content` and leave `summary` empty.
Tests cover the raw thinking appearing exactly once in the emitted stream.
Usage records show a reasoning badge next to the model name for OpenAI and
Claude requests, but Gemini requests never got one. The extraction only read
the OpenAI/Claude shapes (`reasoning_effort`, `reasoning.effort`,
`output_config.effort`), while Gemini states its reasoning depth inside
`generationConfig.thinkingConfig` — so nothing was written to the usage
metadata and the list and detail views had no badge to render.
Read the Gemini shape too, as a fallback after the existing three so the
OpenAI and Claude paths are untouched:
- `thinkingLevel` / `thinking_level` wins when present, trimmed and
lowercased, with the protobuf enum prefix stripped so `THINKING_LEVEL_HIGH`
resolves like `high`.
- Otherwise `thinkingBudget` / `thinking_budget` goes through the existing
shared budget ladder, yielding the same `low|medium|high|xhigh` vocabulary
the badge already understands.
- Both camelCase and snake_case spellings are read, so a captured client body
and a converted provider body resolve to the same label.
- `includeThoughts` alone is a visibility flag, not a depth, and produces no
badge.
Two cases are handled explicitly rather than through the shared ladder:
- `thinkingBudget: 0` disables reasoning outright. The shared ladder maps
`0..=1664` to `low`, which would report an explicitly disabled request as a
shallow one, so it reports `none` instead.
- `THINKING_LEVEL_UNSPECIFIED` is the enum's "no explicit level" member, not a
depth; it is rejected rather than surfaced as an `unspecified` badge.
The frontend needs no change: `UsageModelDisplay` already renders the badge
whenever the fields are present, and keeps the `high -> xhigh` mapping format
when the requested and upstream efforts differ.
Move Antigravity schema-preservation policy into the format crate and expose provider-aware Chat and Responses builders through the existing gateway root seam. Preserve legacy conversion and scoped Responses history behavior without weakening architecture tests.
Validated: 61 standalone architecture tests, 947 format tests, 527 transport tests, 2 actual-source planner tests, and gateway cargo check.
Preserve tool schemas across provider-scoped format conversion and OpenAI gateway planners until the Antigravity boundary. Bound reference expansion, safely merge schema constraints, and lower unsupported Claude unions.
Drop unsigned historical Claude thinking without changing Gemini behavior. Add cross-format regression fixtures and retain the project's original error output policy.
Validation: 945 format tests and 527 transport tests passed; gateway cargo check passed.
stabey