## What changed
- Read `x-codex-imagegen-request-id` from image generation and edit responses.
- Propagate the ID to `codex_image_generation_event` analytics.
- Keep the ID in process only, excluding it from extension item serialization, generated types, app-server wire data, and rollout history.
## Testing
- Cover response-header extraction and missing-header behavior in the images client.
- Verify end-to-end analytics emission and the unchanged image-generation item wire shape.
GitOrigin-RevId: 9b8e09b7d655c0c2faa84f0eee99aabae583668d
## What changed
- Add structured `usageLimitExceeded` metadata to failed image-generation
items, including the image limit ID and optional reset timestamp.
- Preserve the failure metadata in completion events, app-server thread
history, thread reads and resumes, and migrated legacy rollouts.
- Export the new failure type in the generated JSON and TypeScript schemas.
## Testing
- Cover usage-limit responses through item completion, persistence, and thread
resume.
- Verify legacy rollout migration retains image-generation failure metadata.
GitOrigin-RevId: 91c31a2a47456b6b916ee03002ff314b05946dd4
## What changed
- Add `transparentBackground` to image-generation items and legacy completion events.
- Map Images API backgrounds to `true` for transparent, `false` for opaque, and `null` for automatic or unavailable values.
- Preserve the metadata in live notifications and persisted or resumed thread history while continuing to deserialize older items that omit it.
## Testing
- Cover transparent, opaque, and automatic backgrounds, including image edits and thread read/resume flows.
- Verify the stable JSON shape and optional TypeScript field.
GitOrigin-RevId: 08527f37f23431df45fab1ed34eb82b2139b49d7
## Description
This PR adds a `codex-extension-items` crate for extension-owned
`TurnItem` schemas, and updates standalone image generation to start
using it via `TurnItem::Extension`.
This gives us a way to prevent Core from having to be aware of all
extension items. App-server still exposes the existing public
`ThreadItem::ImageGeneration` shape, now by wrapping the same shared
`image_generation::ImageGenerationItem` type.
The new `codex-extension-items` crate is necessary because the image gen
extension item is used by:
- `codex-image-generation-extension`, which produces it.
- `codex-tools / core`, which carry it generically.
- `codex-protocol`, which serializes it into lifecycle events and
rollouts.
- `app-server protocol`, which wraps it in public
`ThreadItem::ImageGeneration`
```
extension implementation
↓
codex-extension-items
↓
protocol / tools / app-server
```
We keep the hosted Responses API image generation as
`TurnItem::ImageGeneration` because core still owns its persistence and
legacy fanout.
### Before
Standalone image generation is implemented as an extension, but its item
representation previously lived in the core protocol. This sets the
precedent that core is aware of all extension items, which would be good
to avoid.
```
image-gen extension
→ constructs codex_protocol::ImageGenerationItem
→ emits ExtensionTurnItem::ImageGeneration
→ core matches ImageGeneration specially
→ protocol stores TurnItem::ImageGeneration
```
### After
```
image-gen extension
→ constructs extension-owned ImageGenerationItem
→ emits generic ExtensionItem
→ core transports/persists it generically
→ app-server wraps ImageGenerationItem as ThreadItem::ImageGeneration
```
Future extension items can have typed app-server APIs without adding a
new `TurnItem` variant, `ExtensionTurnItem` variant, or core emitter
match arm.
## What changed
- Added `codex-extension-items` with the closed `ExtensionItem` enum and
shared `image_generation::ImageGenerationItem` schema.
- Added generic `TurnItem::Extension(ExtensionItem)` and
`ExtensionTurnItem::Extension { item, legacy_events }` paths.
- Updated standalone image generation to emit a typed extension item and
provide its existing legacy `ImageGenerationBegin` /
`ImageGenerationEnd` events explicitly.
- Kept canonical lifecycle ordering: core emits `ItemStarted` /
`ItemCompleted` before extension-provided legacy events.
## Follow-up
Standalone web search still uses its typed special-case path. Migrating
it later would let `ExtensionTurnItem` collapse into a single
extension-item struct.
Chris Dong