## Stack
1. [#26547](https://github.com/openai/codex/pull/26547) - [1 of 2] Align
goal extension with core behavior
2. [#26548](https://github.com/openai/codex/pull/26548) - [2 of 2] Move
goal runtime to extension
## Why
The goal runtime is moving out of `codex-core` and into
`codex-goal-extension`. This first PR brings the extension back in line
with the current core behavior before the follow-up PR switches
app-server sessions over to the extension, so that review can focus on
ownership and wiring rather than hidden behavior drift.
## What Changed
- Updates the extension `create_goal` and `update_goal` tool
schemas/descriptions to match the current core wording for explicit
token budgets, blocked-goal audits, resumed blocked goals, and
system-owned budget/usage-limit transitions.
- Marks `codex-goal-extension` as the live `/goal` extension crate
rather than an unwired sketch.
- Looks up the live thread before reading goal state for idle
continuation, so continuation setup exits early when no live thread can
accept the automatic turn.
## Why
The goal extension can create and surface goals, but the live
turn-accounting path still stopped short of persisting active-goal
progress. That leaves token and wall-clock usage, plus
`ThreadGoalUpdated` events, out of sync with the extension boundary once
work actually advances or a goal transitions out of active state.
## What changed
- Teach `GoalAccountingState` to track the current turn, active goal,
token deltas, and wall-clock progress snapshots against the persisted
goal id.
- Flush active-goal accounting from tool-finish, turn-stop, and
turn-abort lifecycle hooks, and emit `ThreadGoalUpdated` events when
persisted progress changes.
- Route `create_goal` and `update_goal` through the same accounting
state so new goals start from the right baseline, final progress is
flushed before status changes, and `update_goal` can mark a goal
`blocked` as well as `complete`.
- Keep budget-limited goals accruing through the end of the turn while
clearing local active-goal state once a turn or explicit update is
finished.
- Expand backend and lifecycle coverage around store ids, baseline
reset, tool-finish accounting, budget-limited carry-through, and
blocked-goal updates.
## Testing
- Added focused backend coverage in
`codex-rs/ext/goal/tests/goal_extension_backend.rs` for baseline reset,
tool-finish accounting, budget-limited turns, and blocked-goal updates.
- Extended `codex-rs/core/src/session/tests.rs` to assert that lifecycle
inputs expose the expected session, thread, and turn store ids.
Eric Traut