Add compile-time behavioral consistency checks

## Problem statement The compiler needs a deterministic check that generated artifacts still match the behavioral model before running package export/import or provider materialization checks. ## Scope - Verify every modeled workflow step appears in generated `WORKFLOW.md` step order. - Verify every modeled skill, agent, policy, reference, setup requirement, and validation gate is represented or explicitly marked as intentionally omitted. - Verify evidence links remain traceable from generated artifacts back to the behavioral model. - Report missing, extra, reordered, or ambiguous generated behavior. ## Acceptance criteria - Consistency checks pass for a representative compiled package. - Checks fail clearly when a step is omitted, reordered, or points to a missing skill. - Checks fail when required references or setup requirements are absent. - Tests cover pass, missing step, reordered step, missing reference, and intentionally omitted item cases. ## Dependencies - Depends on the behavioral model and provider-neutral artifact generation. - Complements #49 but runs before workflow execution. ## Non-goals - No live provider launch. - No package export/import round trip. - No subjective content scoring. ## Sequencing First child issue in behavioral validation. Later validation issues should call this before deeper checks.