Doc to code map
- docs/spec/read_this_first.md → src/bijux_vex/core
- docs/spec/execution_contracts.md → src/bijux_vex/core/contracts, src/bijux_vex/domain/execution_requests
- docs/spec/failure_semantics.md → src/bijux_vex/core/errors, src/bijux_vex/core/failures.py
- docs/spec/execution_lifecycle.md → src/bijux_vex/core/runtime, src/bijux_vex/domain/execution_requests
- docs/spec/execution_artifacts.md → src/bijux_vex/domain/execution_artifacts
- docs/spec/examples → tests/e2e
- docs/spec/system_contract.md → src/bijux_vex
- docs/spec/invariant_ids.md → src/bijux_vex/core/errors/error_types.py
- docs/maintainer/why_this_is_hard.md → docs/maintainer
- docs/spec/mental_model.md → src/bijux_vex/core
- docs/spec/vdb_profile.md → src/bijux_vex
- docs/maintainer/freeze_criteria.md → docs/maintainer
- docs/spec/identity.md → src/bijux_vex
- docs/user/not_a_vdb.md → docs/user
- docs/maintainer/extension_points.md → src/bijux_vex