Seal ATS-1 1.0.0-draft.3 with behavioral AC semantics #4

PR #3 / merge d3b121dfd262b87834b64317e94769718b72a29f accepted D-G after adversarial review. Promote it as a separate sealed normative edition; do not mutate draft.2 in place.

Scope

Create spec/ATS-1/1.0.0-draft.3/ from the sealed draft.2 baseline with only D-G semantic changes:

• §9.3.2: acceptance_criterion = canonical falsifiable behavioral proposition, not evidence.
• §9.3.9: exact REQ↔AC mapping; test/evidence instruments cannot substitute for AC; load-bearing rule; scope-fidelity/no-hidden-obligation rule; normative thresholds remain in REQ/AC.
• §9.3.10 and §9.3.20 wording aligned.
• Add ATS-REQ-004 as review_required, SPECIFY: advisory, TRANSFORM: advisory so current no-D3 implementation does not create a mandatory semantic/model pass.
• D1 may catch structural/test-shaped failures but may not certify load-bearing semantics by absence.

Required evidence before default flip

• behavioral conforming fixture;
• test-shaped negative;
• non-load-bearing negative;
• scope-widening/hidden-obligation negative;
• spec/registry statement identity;
• package manifest and offline validator PASS;
• draft.1 and draft.2 byte identity unchanged;
• repository public gate PASS.

Version law

• normative edition: 1.0.0-draft.3 — yes, this is the appropriate bump;
• implementation: remain 0.5.0 unless implementation code changes materially;
• skill pack: no bump merely for opening the normative edition; bump only if canonical skill bytes/default behavior change;
• DEFAULT_SPEC_VERSION remains draft.1 for historical interpretation;
• do not move AUTHORING_SPEC_VERSION or config/policies/fleet_policy.json from draft.2 until the sealed draft.3 package is validated and imported;
• after that gate, flip new durable authoring to draft.3 in a separate auditable commit/PR and regenerate any policy IDs/derived assets required by the repo.

Non-goals

No schema fields, evidence-planning ontology, failure-mechanism field, new D3 implementation, new mandatory lint pass, or historical corpus migration.