Pier adapter 0.3.8

Pier adapter 0.3.8 preserves terminal Device resource failures as the exported
ReasonSessionResourceUnavailableError. Session, trajectory, usage, and cleanup
evidence remain available. Other failure types keep their existing behavior.

The adapter still resolves and checksum-verifies the current stable Reason CLI
inside each production task. No retry flags or CLI overrides are required.

The accompanying server change can reconcile a missing cancellation
acknowledgement after reconnecting to the same authenticated worker. It never
replays the original command. Work continues only after confirmed settlement;
uncertain outcomes remain errors.

Validation:

• All 337 adapter tests passed against a clean installation of the release wheel.
• Real-worker fault tests verified recovery after a lost result and cancellation
  acknowledgement, subsequent command execution, and exactly one mutation.
• The fault proof also passed three consecutive Linux x64 Docker runs.
• On September 18, 2026, a fresh clone following the public README completed
  the DeepSWE quickstart against production with stable CLI 0.2.61. It had
  zero startup/runtime exceptions, zero trial retries, and no cleanup errors.
  The grader passed 68/79 feature tests and all 16,715 existing tests. Reward
  remained 0 because some feature tests failed.

Built from reason-machines/monorepo commit
d5f4cdf59dfb94f0daaf43a71de138424d29586a, merged in PR #11664.
The examples tag identifies the example repository; the adapter source is the
monorepo commit above. SHA256SUMS covers both attached packages.

A completed benchmark run can still fail task tests.