What's new

Previously failed tests:

• prefetches session additional skill roots...: expected roots on skills/list, but Codex now uses skills/extraRoots/set.
• should send attachments as prompt items: snapshot still had removed perCwdExtraUserRoots.
• should fail on wrong sessionId: Codex now reports invalid session id instead of invalid thread id.

Changed:

• Added skills/extraRoots/set client support and moved additional skill roots there before skills/list.
• Normalized string service tiers back to ACP’s supported fast/flex values.
• Added explicit no-op handling for new app-server notifications.
• Updated test fixtures for new generated type fields: model service tiers, turn itemsView, thread/session identifiers, MCP serverInfo, approval timestamps, rate limit individualLimit, and thread item fields.