v1.6.0

Added

• Goal contracts — an acceptance criterion is now a typed evidence requirement over a code
  component (verification, tests, or decomposition), and a goal carries its own policy bar.
  State the goal as a contract - accomplish these things, subject to these policies - and
  ponens trace enrich returns three independent verdicts: met (criteria resolved from evidence),
  governed (the goal's policies held), and certified (a non-doer confirmed the criteria were
  the right ones). Author the whole contract in one shot with ponens trace goal set --json. See the
  new GOAL_CONTRACT_v0_1 spec.
• Goal-scoped policies — the governed axis — a goal can name policy packs and policies; they
  block by default unless explicitly disabled (recorded on the trace, never silent). Pack names
  resolve against the registry, and enrich attaches the governance result per goal.
• Artifact lineage / provenance API — a new dependency-free ponens.lineage module answers what a
  specific artifact was derived from: ancestor_ids, lineage_types, source_symbols, autoformalized,
  decomposition_backed, and a one-call provenance summary.

Changed

• ponens agent now teaches the goal-contract workflow — typed criteria, the goal's policy bar, and
  the three axes (met / governed / certified), including the rule that the agent proposes the rigor bar
  while a human selects it, and never self-certifies.
• ponens trace enrich now reports the governed axis alongside met and certified.

Fixed

• Goals now reach met when the work is real — a typed criterion resolves by artifact lineage
  (does a proved result for this property trace back to a model autoformalized from this component?)
  instead of matching the verification goal's description text. This fixes goals that never ticked even
  though the property was proved, and stops a similarly-worded but unrelated result from satisfying a
  criterion.