Publish portable Agent Gearbox core

[sneakocom]

Summary

• establish the canonical primary-developer Gearbox boundary
• publish a provider-free Python reference core with deterministic and injected-helper gears
• preserve exact Taslos Tasks provenance and AGPL licensing without product or Durable Supervisor code
• add provider-free tests, CI, benchmark limits, and revision-bound release evidence

Verification

• tools/verify (19 tests)
• ruff check src tests tools/dogfood
• shellcheck tools/verify
• actionlint .github/workflows/ci.yml
• gitleaks detect --no-banner --no-git --source .
• uv build --wheel
• opsle/research value-receipt validator
• release artifact locator/hash verification

Scope boundary

No production provider transport, retry/fallback controller, durable orchestration, product state, credentials, or private evidence is included. The source Taslos Tasks repository was not modified.