Use provider-reported rollout budget units (#36715)

## What changed

- Charge `codex_rollout_budget_units` against the shared rollout budget when the provider includes it in response usage.
- Fall back to weighted input and output token accounting when provider units are absent.
- Reject non-finite or negative provider units as a fatal response error.

## Testing

- Cover provider units in reminder thresholds and local and remote compaction budget exhaustion.
- Verify invalid units fail without retrying the response.

GitOrigin-RevId: b452403e365985854d16f298d1ba46383e9892c4

codex-rs/core/src/session/rollout_budget.rs

@@ -28,7 +28,7 @@ impl Session {
             .services
             .agent_control
             .rollout_budget()
-            .record_usage(usage)
+            .record_usage(usage)?
         {
             return Err(CodexErr::SessionBudgetExceeded);
         }