End-to-end reconciliation parity gate vs frozen views-reporting

[Polichinel]

Epic: #31 · Depends on: #36

Background

The gate that turns "leaf ported" into "pipeline migrated." Slice 1 proved the leaf; this proves the whole orchestration reproduces the frozen views-reporting pipeline end-to-end. This is epic acceptance criterion #1.

Work

• Using the S0 fixture (cm + pgm + injected mapping + the oracle's reconciled pgm), assert our ReconciliationModule reproduces the oracle's reconciled pgm output (bit-exact, or a tight, documented tolerance).
• Add module-level property tests: per-(country, time, draw) sum constraint, zeros preserved, non-negativity, de-mutation.

Acceptance criteria

• End-to-end parity green offline (CI needs no torch / views-reporting / viewser).
• Property tests pass.
• Any tolerance is documented with the float32 rationale (slice-1 parity was exact, so expect ~exact).

Validation

• pytest tests/test_reconciliation_e2e_parity.py green; full suite stays green.