Prevent FE and BE from overwriting the shared build report #45

Area

Pipeline / agents / build artifacts

Problem

The build stage supports parallel frontend and backend work, but both specialists are instructed to write the same report:

• Frontend agent: write to .team/07-build.md.
• Backend agent: write to .team/07-build.md.
• Build stage: FE is the primary agent, BE is support, and their work can run in parallel.

Their memory logs are separate, but this shared artifact still has two writers. Concurrent or successive writes can overwrite a specialist's findings, tests, or outstanding work, and the report alone does not establish that both specialists finished successfully.

This is an instruction/configuration conflict found by source inspection; an actual lost write has not yet been reproduced in a live pipeline run.

Proposal

Have FE and BE write separate reports, such as .team/07-build-fe.md and .team/07-build-be.md. The orchestrator should be the sole writer of the consolidated .team/07-build.md, combining the requested specialists' results after successful completion.

For builds that dispatch both FE and BE, wait for both results before presenting the stage as complete. Failed, cancelled, or missing results should keep the stage incomplete and explain what remains.

Acceptance criteria

• FE and BE no longer write directly to the same build report.
• Both specialist reports retain implementation details, test evidence, and unresolved items.
• The orchestrator aggregates only after every specialist requested for that build has completed successfully.
• An unfinished or failed specialist cannot cause the build gate to be reported as completed.
• The consolidated report references both source reports; rerunning aggregation does not duplicate sections or discard results.
• QA continues to consume the consolidated .team/07-build.md.
• Agent instructions, build playbook, docs, and generated references are consistent.
• Verification covers parallel completion, one failed/pending specialist, and rerunning aggregation.

Alternatives considered

Serializing both agents would reduce simultaneous writes but retain two owners of the same artifact and give up useful parallel work.

Compatibility

Keep .team/07-build.md as the public build-stage artifact. Treat the specialist reports as intermediate outputs, and do not skip existing human approval gates.