CBM-021 — Reproducible CI and migration matrix

[Martin-Hausleitner]

Source: immutable masterplan

Priority: P0
Files: Modify pyproject.toml and test scripts; create backend/requirements-dev.txt, .github/workflows/ci.yml, Docker smoke configuration, and CI documentation.

• Declare test-only pytest/asyncio/trio dependencies so asyncio_mode is reproducible.
• Run backend unit/API/migration races, worker contracts, frontend tests/build, lint/typecheck, secret scan, feature manifest, and Docker smoke.
• Test fresh DB, each supported legacy migration fixture, concurrent startup, and rollback backup.
• Upload screenshots, traces, benchmark JSON, and logs as artifacts with secret scans.
• Block releases on unknown env flags, missing worker versions, schema skew, low disk, or stale visual evidence.
• Commit as ci: Add reproducible release evidence matrix.

Acceptance: The same command produces the same full green suite on developer Mac, CI, and the release checkout.

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This ticket is part of the dependency-ordered universal control-plane program. Do not weaken its safety exclusions or acceptance gate.

[Martin-Hausleitner]

Implemented on feature/browser-use-agent-workspace in b3730bd. CI now has schema/env/version/disk, backend, migration, frontend, build, Ruff, secret-scan, and Docker-smoke lanes with artifacts. Evidence: actionlint and compose config pass; combined Python suite 995 passed; frontend 169 passed; production build and Ruff passed. Held open until merge/release.