v1.2.11

• breaking: remove qexp v1 compatibility shims and the transitional qqtools.plugins.qexp.v2 package surface; only the unified shared-root qexp API/CLI remains
• feat: add qexp resubmit to replace one terminal non-batch task in place with the same task_id, persist resubmit operation truth, and surface unfinished replacement state through inspect
• feat: add qexp doctor repair to converge unfinished resubmit operations and repair batch metadata inconsistencies in one recovery entrypoint
• fix: reconcile qexp batch commit-state truth so incomplete preparing batches are repaired to committed or aborted with refreshed batch summaries and indexes
• feat: fail qpipeline runs with reason=nan_detected when periodic eval/save boundaries observe NaN training loss
• feat: synchronize NaN-failure signals across DDP ranks and report source ranks from rank0 logs before unified failed exit
• docs: sync qexp README/manual/specs with the unified shared-root package surface, project-root .qexp contract, group semantics, resubmit, and doctor repair
• docs: add qpipeline timing manual and update log-format docs for periodic NaN interception behavior
• test: add qexp coverage for unified package surface, doctor integrity/repair flows, batch commit-state reconciliation, and resubmit transaction semantics
• test: add functional coverage for NaN terminal events, periodic interception, and distributed NaN-failure signal synchronization